Insects Sentence Examples

The night was quiet, no insects chirping, no water gurgling.

This is easy to happen with plants dependent on insects for their fertilization.

I was never still a moment; my life was as full of motion as those little insects that crowd a whole existence into one brief day.

Outside of snakes and insects, there was nothing dangerous about the forest.

I am studying about insects in zoology, and I have learned many things about butterflies.

The minute insects included in it, which haunt blossoms and leaves, are fairly well known to gardeners by the name Thrips, a generic term used by Linnaeus for the four species of the group which he had examined and relegated to the order Hemiptera.

After examining a rock for ants or other insects, she leaned against it, drawing in the clean smell of the forest.

The usual variations in habit that characterize plant-feeding insects are exhibited by the Thysanoptera some species being found only on one particular food-plant, while others thrive indifferently on a large assortment.

The latter raises the moss and bark gently with his knife in search of insects; the former lays open logs to their core with his axe, and moss and bark fly far and wide.

The snakelike branches overhead were creepier when she could see them in daylight, and the few birds and insects she saw made her shudder.  The sense of being followed didn't leave even in the full light of day.

As the light faded from the treetops, the birds grew silent and insects began their orchestra of night sounds.

When we use pesticides, we kill them as well as the harmful insects - and even the bees.

The inhabitants of tropical America sometimes keep fireflies in small cages for purposes of illumination, or make use of the insects for personal adornment.

Ustilago, and filling a greenhouse with hydrocyanic acid gas when young insects are commencing their ravages, e.g.

The extraordinary forms, colors and textures of the true galls have always formed some of the most interesting of biological questions, for not only is there definite co-operation I between a given species of insect and of plant, as shown by the facts that the same insect may induce galls of different kinds on different plants or organs, while different insects induce different galls on the same plante.g.

Insects abound, especially Coleoptera.

In other insects the imaginal disks are less completely disconnected from the superficies of the larval hypodermis, and may indeed be merely patches thereof.

These changes are in the higher insects so extreme that it is difficult to imagine how they could be increased.

Armadillos are omnivorous, feeding on roots, insects, worms, reptiles and carrion, and are mostly, though not universally, Peba Armadillo (Tatusia novemcincta).

Among the early writings, besides the book of Curtis, there may also be mentioned a still useful little publication by Pohl and Kollar, entitled Insects Injurious to Gardeners, Foresters and Farmers, published in 1837, and Taschenberg's Praktische Insecktenkunde.

Linnaeus in his Systema naturae (1735) grouped under the class Insecta all segmented animals with firm exoskeleton and jointed limbs - that is to say, the insects, centipedes, millipedes, crustaceans, spiders, scorpions and their allies.

Not to speak of insects which feed upon the pitcher itself, some drop their eggs into the putrescent mass, where their larvae find abundant nourishment, while birds often slit open the pitchers with their beaks and devour the maggots in their turn.

Much has been done in keeping out the insects by fine wire netting placed on the windows and the doors of houses, especially in the railwaymens cottages.

The beetles are elegant insects with long, slender legs, running quickly, and flying in the sunshine.

Amongst insects with imperfect metamorphosis the nearest approximations to the true pupa of the Holometabola are to be found in the subimago a From Chittenden, Bull.

The occurrence of weevils - among the most specialized of the Coleoptera - in Triassic rocks shows us that this great order of metabolous insects had become differentiated into its leading families at the dawn of the Mesozoic era, and that we must go far back into the Palaeozoic for the origin of the Endopterygota.

One genus of Thomisidae (Phognarachne), which inhabits the Oriental region, adopts the clever device of spinning on the surface of a leaf a sheet of web resembling the fluid portions of a splash of bird's dung, the more solid central portions being represented by the spider itself, which waits in the middle of the patch to seize the butterflies or other insects that habitually feed on birds' excrement and are attracted to the patch mistaking it for their natural food.

Under such conditions the deeply-rooted nature of the blood-sucking instinct is most remarkable; for insects whose ancestors for many generations may not have tasted blood will seek for it with the utmost keenness and pertinacity so soon as an opportunity presents itself.

The larvae are perfectly white at first and wingless, although in other respects not unlike their parents, but they are not mature insects until after the sixth casting of the skin.

The passage at first runs obliquely upwards in the bank, sometimes to a distance of as much as 50 ft., and expands at its termination into a cavity, the floor of which is lined with dried grass and leaves, and in which, it is said, the eggs are laid' and the young brought up. Their food consists of aquatic insects, small crustaceans and worms, which are caught under water, the sand and small stones at the bottom being turned over with their bills to find them.

Other industries of a desultory character include the collection of archil, or Spanish moss, on the western side of the Californian peninsula, hunting herons for their plumes and alligators for their skins, honey extraction (commonly wild honey), and the gathering of cochineal and ni-in insects.

Troublesome insects, vampire bats, and the failure to introduce new blood into the degenerated herds, are responsible for its decline.

It is possibly for the purpose of feeding on parasitic mites that book-scorpions lodge themselves beneath the wing-cases of large tropical beetles; and the same explanation, in default of a better, may be extended to their well-known and oft-recorded habit of seizing hold of the legs of horse-flies or other two-winged insects.

In ordinary language the name is used for any species of Siphonaptera (otherwise known as Aphaniptera), which, though formerly regarded as a suborder of Diptera, are now considered to be a separate order of insects.

The structure of the mouth-parts is different from that seen in any other insects.

In general it may be stated that beetles live and feed in almost all the diverse ways possible for insects.

Various species among those that are predaceous attack smaller insects, hunt in packs crustaceans larger than themselves, insert their narrow heads into snail-shells to pick out and devour the occupants, or pursue slugs and earthworms underground.

The Coleoptera can be traced back farther in time than any other order of insects with complete transformations, if the structures that have been described from the Carboniferous rocks of Germany are really elytra.

The Coleoptera have been probably more assiduously studied by systematic naturalists than any other order of insects.

In recent years classifications in part agreeing with the older schemes but largely original, in accord with researches on the comparative anatomy of the insects, have been put forward.

Kolbe, on the other hand, insists that the weevils are the most modified of all beetles, being highly specialized as regards their adult structure, and developing from legless maggots exceedingly different from the adult; he regards the Adephaga, with their active armoured larvae with two foot-claws, as the most primitive group of beetles, and there can be little doubt that the likeness between larvae and adult may safely be accepted as a primitive character among insects.

The generalized arrangement of the wing-nervure and the nature of the larva, which is less unlike the adult than in other beetles, distinguish this tribe as primitive, although the perfect insects are, in the more dominant families, distinctly specialized.

Many of our native species spend the day lurking beneath stones, and sally forth at night in pursuit of their prey, which consistsof small insects, earthworms and snails.

Beetles and larvae are frequently carnivorous in habit, hunting for small insects under stones, or pursuing the soft-skinned grubs of beetles and flies that bore in woody stems or succulent roots.

The males are very small, free-flying insects with the prothorax, mesothorax and elytra greatly reduced, the latter appearing as little, twisted strips, while the metathorax is relatively large, with its wings broad and capable of longitudinal folding.

During summer the insects rest in their underground retreats, then in autumn FIG.

Like the perfect insects, they are predaceous, feeding on plant-lice (Aphidae) and scale insects (Coccidae).

C. Miall's Aquatic Insects (London, 1895), the special literature of the Coleoptera is enormous.

The various species of rapacious animals are disappearing, together with the colonies of marmots; the insectivores are also becoming scarce in consequence of the destruction of insects; while vermin, such as the suslik, or pouched marmot (Spermophilus), and the destructive insects which are a scourge to agriculture, become a real plague.

The -fact that the name of the ant has come down in English from a thousand years ago shows that this class of insects impressed the old inhabitants of England as they impressed the Hebrews and Greeks.

An ant is easily recognized both by the casual observer and by the student of insects.

It is this peculiar " waist " that catches the eye of the observer, and makes the insects so easy of recognition.

Other insects visit the flower with more questionable result.

These illustrations are comparatively simple; it would have been easy to select others of a more complicated nature, but all evidently connected with the visits of insects and the cross fertilization of the flower.

The insects of all southern Asia, including India south of the Himalaya, China, Siam and the Malayan Islands, belong to one.

Of Coleopterous insects known to inhabit east Siberia, nearly one-third are found in western Europe.

Yet these figures are nothing compared to the losses due to scale insects, locusts and other pests.

The most able exponent of this subject in Great Britain was John Curtis, whose treatise on Farm Insects, published in 1860, is still the standard British work dealing with the insect foes of corn, roots, grass and stored corn.

American literature began as far back as 1788, when a report on the Hessian fly was issued by Sir Joseph Banks; in 1817 Say began his writings; while in 1856 Asa Fitch started his report on the " Noxious Insects of New York."

Lintner extend from 1882 to 1898, in yearly parts, under the title of Reports on the Injurious Insects of the State of New York.

The insects in the larval or wireworm stage attack the roots of plants, eating them away below the ground.

These insects pass the pupal stage in the ground, and reach the boughs to lay their eggs by crawling up the trunks of the trees.

By far the most destructive insects in warm climates belong to the Hemiptera, especially to the Coccidae or scale insects.

All fruit and forest trees suffer from these curious insects, which in the female sex always remain apterous and apodal and live attached to the bark, leaf and fruit, hidden beneath variously formed scale-like coverings.

Other scale insects of note are the cosmopolitan mussel scale (Mytilaspis pomorum) and the Australian Icerya purchasi.

A, Winged female; B, winged D, viviparous wingless female from in patches from old apple trees, where the insects live in the rough bark and form cankered growths both above and below ground.

Amongst Orthoptera we find many noxious insects, notably the locusts, which travel in vast cloud-like armies, clearing the whole country before them of all vegetable life.

For insects provided with a biting mouth, which take nourishment from the whole leaf, shoot or fruit, the poisonous washes used are chiefly arsenical.

Willughby, Ray and others in the late 17th century to include the active larvae of beetles, as well as bugs, lice, fleas and other insects with undeveloped wings.

The compound eyes of insects resemble so closely the similar organs in Crustaceans that there can hardly be reasonable doubt of their homology, and the primitively appendicular nature of the eyes in the latter class suggests that in the Hexapoda also they represent the appendages of an anterior (protocerebral) segment.

The thorax is composed of three segments; each bears a pair of jointed legs, and in the vast majority of insects the two hindmost bear each a pair of wings.

The wings of insects are, in all cases, developed after hatching, the younger stages being wingless, and often unlike the parent in other respects.

Exoskeleton The outer cellular layer (ectoderm or " hypodermis ") of insects as of other Arthropods, secretes a chitinous cuticle which has to be periodically shed and renewed during the growth of the animal.

On either side a variable amount of convex area is occupied by the compound eye; in many insects of acute sense and accurate flight these eyes are very large and sub-globular, almost meeting on the middle line of the head.

Elaboration in the form of the feelers, often a secondary sexual character in male insects, may result from a distal broadening of the segments, so that the appendage becomes serrate, or from the development of processes bearing sensory organs, so that the structure is pinnate or feather-like.

In most insects that feed by suction the mandibles are modified.

As previously mentioned, a pair of minute jaws - the maxillulae- are present in the lowest order of insects, between the mandibles and the first maxillae.

Such maxillae are found in most biting insects.

In insects whose mouths are adapted for sucking and piercing, remarkable modifications may occur.

In generalized biting insects, such as cockroaches and locusts (Orthoptera), the parts of a typical maxilla can be easily recognized in the labium.

In specialized biting insects, such as beetles (Coleo C ptera), the labium tends to become a hard transverse plate bearing the pair of palps, a median structure - known as the ligula - formed of the conjoined laciniae, and a pair of small rounded processes - the reduced galeae - often called the " paraglossae," a term better avoided since it has been applied also to the maxillulae of Aptera, entirety different structures.

A median process, known as the hypopharynx or tongue, arises from the floor of the mouth in front of the labium, and becomes most variously developed or specialized in different insects.

Two pairs of wings are present in the vast majority of insects, borne respectively on the mesothorax and metathorax.

In addition to the wings there are smaller dorsal outgrowths of the thorax in many insects.

Paired erectile plates (patagia) are borne on the prothorax in moths, while in moths, sawflies, wasps, bees and other insects there are small plates (tegulae) - see Fig.

Most insects possess a pair of compound eyes, and many have, in addition, three simple eyes or ocelli on the vertex.

These tubes vary in number from four to over a hundred in different orders of insects.

In various groups of the Hexapoda - aphids and some flesh-flies (Sarcophagi), for example - the egg undergoes development within the body of the mother, and the young insect is born in an active state; such insects are said to be " viviparous."

In insects so widely separated as bristle-tails and moths this occurs occasionally.

These two endoderm-rudiments embryonic membrane formed by delamination from the blastoderm, ultimately grow together and give rise to the epithelium of the midwhile in a few insects, including the wingless spring-tails, the emgut.

Schwangart, who has studied (1904) the embryonic insects, twenty-one of these divisions - not, however, all similar - development of Lepidoptera.

It has been disputed whether any true cerci exist in the higher insects, but they are probably represented in the Diptera and in the scorpionflies (Mecaptera).

In those insects in which a median terminal appendage exists between the two cerci this is considered to be a prolongation of the eleventh tergite.

This has been found to be the case in insects so widely different as Orthoptera and Aculeate Hymenoptera.

In the embryos of many insects there are projections from the segments of the abdomen similar, to a considerable extent, to the rudimentary thoracic legs.

The question whether these projections can be considered an indication of former polypody in insects has been raised.

Wingless insects, such as spring-tails and lice, make their appearance in the form of miniature adults.

Sharp (1898), the marked divergence among the Hexapoda, as regards life-history, is between insects whose wings develop outside the cuticle (Exopterygota) and those whose wings develop inside the cuticle (Endopterygota), becoming visible only when the casting of the last larval cuticle reveals the pupa.

It is different in its details in different insects and in different stages of the life of the same insect.

It has, however, since been found that in other kinds of insects the tissues degenerate and break down without the intervention of phagocytes.

Much consideration has been given to the nature of metamorphosis in insects, to its value to the creatures and to the mode of its origin.

It is instructive, further, to trace among metabolic insects an increase in the degree of this dissimilarity.

The term nymph is applied by many writers on the Hexapoda to all young forms of insects that are not sufficiently unlike their parents to be called larvae.

If we admit that the larva has, in the phylogeny of insects, gradually diverged from the imago, and if we recollect that in the ontogeny the larva has always to become the imago (and of course still does so) notwithstanding the increased difficulty of the transformation, we cannot but recognize that a period of helplessness in which the transformation may take place is to be expected.

Moreover, in many insects with imperfect metamorphosis the change from larva or (as the later stage of the larva is called in these cases) nymph to imago is about as great as the corresponding change in the Holometabola, as the student will recognize if he recalls the histories of Ephemeridae, Odonata and male Coccidae.

For details, the reader may consult the special articles on the various orders and groups of insects.

The extreme of this " division of labour " is seen, in those insects whose jaws are vestigial in the winged state, when, the need for feeding all behind them, they have but to pair, to lay eggs and to die.

In the egg of these insects a small number of nuclei are formed by the division of the nucleus, and each of these nuclei originates by division the cell-layers of a separate embryo.

Although one of the characteristics of insects is the brevity of their adult lives, a considerable number of exceptions to the general rule have been discovered.

In addition to these abnormal cases, the life of certain insects is naturally more prolonged than usual.

The females of some social insects have been known to live for many years.

The greater part by far of the insects existing in the world is still quite unknown to science.

As regards the vast majority of insects, the orders proposed by Linnaeus are acknowledged by modern zoologists.

His order of wingless insects (Aptera) included Crustacea, spiders, centipedes and other creatures that now form classes of the Arthropoda distinct from the Hexapoda; it also included Hexapoda of parasitic and evidently degraded structure, that are now regarded as allied more or less closely to various winged insects.

Sharp's proposed association of the parasitic wingless insects in a group Anapterygota cannot, however, be defended as natural; and recent researches into the structure of these forms enables us to associate them confidently with related winged orders.

These minute insects are found amongst old books and furniture.

See Neuroptera, among which these insects were formerly comprised.

Geological History The classification just given has been drawn up with reference to existing insects, but the great majority of the extinct forms that have been discovered can be referred with some confidence to the same orders, and in many cases to recent families.

The Hexapoda, being aerial, terrestrial and fresh-water animals, are but occasionally preserved in stratified rocks, and our knowledge of extinct members of the class is therefore fragmentary, while the description, as insects, of various obscure fossils, which are perhaps not even Arthropods, has not tended to the advancement of this branch of zoology.

Several Silurian fossils have been identified as insects, including a Thysanuran from North America, but upon these considerable doubt has been cast.

The latter has established, for all the Palaeozoic insects, an order Palaeodictyoptera, there being a closer similarity between the fore-wings and the hind-wings than is to be seen in most living orders of Hexapoda, while affinities are shown to several of these orders - notably the Orthoptera, Ephemeroptera, Odonata and Hemiptera.

It is probable that many of these Carboniferous insects might be referred to the Isoptera, while others would fall into the existing orders to which they are allied, with some modification of our present diagnoses.

Of special interest are cockroachlike forms, with two pairs of similar membranous wings and a long ovipositor, and gigantic insects allied to the Odonata, that measured 2 ft.

Most of the families and a large proportion of the genera of insects are exceedingly widespread, but a study of the genera and species in any of the more important families shows that faunas can be distinguished whose headquarters agree fairly with the regions that have been proposed to express the distribution of the higher vertebrates.

Many insects, however, can readily extend their range, and a careful study of their distribution leads us to discriminate between faunas rather than definitely to map regions.

Neotropical and distinctively Sonoran insects mingle with members of the Holoarctic fauna across a wide " transition zone " in North America.

The Australian fauna is rich in characteristic and peculiar genera, and New Zealand, while possessing some remarkable insects of its own, lacks entirely several families with an almost world-wide range - for example, the Notodontidae, Lasiocampidae, and other families of Lepidoptera.

After the determination of a number of cosmopolitan insects that may well have been artificially introduced, there remains a large proportion of endemic species - sometimes referable to distinct genera - which suggest a high antiquity for the truly insular faunas.

Brauer, that the Thysanura represent more nearly than any other existing insects the ancestors of the class, has been accepted by the great majority of students.

The caterpillar, or the maggot, is a specialized larval form characteristic of the most highly developed orders, while the campodeiform larva is the starting-point for the more primitive insects.

It is now, in fact, generally admitted that metamorphosis has been acquired comparatively recently, and Scudder in his review of the earliest fossil insects states that " their metamorphoses were simple and incomplete, the young leaving the egg with the form of the parent, but without wings, the assumption of which required no quiescent stage before maturity."

Of existing insects 90% belong to the Endopterygota.

Endopterygota - of insects of the present epoch are descended from the predominant - if not the sole - group that existed in the Palaeozoic epoch, viz.

The first hypothesis is not negatived by direct evidence, for we do not actually know the ontogeny of any of the Palaeozoic insects; it is, however, rendered highly improbable by the modern views as to the nature and origin of wings in insects, and by the fact that the Endopterygota include none of the lower existing forms of insects.

This last state is very frequent in Blattidae, which were amongst the most abundant of Palaeozoic insects.

The wingless forms in question are always allied to winged forms, and there is every reason to believe that they have been really derived from winged forms. There are also insects (fleas, &c.) in which metamorphosis of a " complete " character exists, though the insects never develop wings.

These cases render it highly probable that insects may in some circumstances become wingless, though their ancestors were winged.

Such insects have been styled anapterygotous.

In fact, almost every condition that is required for the change from exopterygotism to endopterygotism exists among the insects that surround us.

It is believed that insects of this group are represented among Silurian fossils.

We have undoubted fossil evidence that winged insects lived in the Devonian and became numerous in the Carboniferous period.

These ancient Exopterygota were synthetic in type, and included insects that may, with probability, be regarded as ancestral to most of the existing orders.

As shown by the number and variety of species, the Orthoptera are the most dominant order of this group. Eminently terrestrial in habit, the differentiation of their fore-wings and hindwings can be traced from Carboniferous, isopteroid ancestors through intermediate Mesozoic forms. The Plecoptera resemble the Ephemeroptera and Odonata in the aquatic habits of their larvae, and by the occasional presence of tufted thoracic gills in the imago exhibit an aquatic character unknown in any other winged insects.

This latter order, which is not certainly known to have existed before Tertiary times, has become the most highly specialized of all insects in the structure of the pupa.

Snares of another type consisting of a tangled mass of threads amongst which the spiders pick their way with ease, but which are impassable to insects, are spun by members of the Theridiidae and Pholcidae; but by common consent the so-called orbicular web, so characteristic of the Argyopidae but by no means confined to them, is regarded as manifesting the greatest perfection of instinct in snare-spinning.

Its whereabouts is thus, to a great extent, concealed both from enemies searching for spiders and from insects suitable for food; and its open meshwork of strong threads makes it much less liable to be beaten down by rain or torn to shreds by winds than if it were a flat sheet of closely woven silk.

Many Thomisidae lurk amongst the stamens and petals of flowers, which they closely match in colour, waiting to seize the insects which visit the blossoms for nectar.

In northern and temperate latitudes where insects disappear in the winter, species of Argyopidae like Aranea diademata, live only for a single season.

The primary function of this poison is to kill the prey upon which they feed, its action being very rapid upon insects.

No doubt large numbers are devoured by insectivorous birds, mammals and reptiles, but the mortality due to them and other foes sinks into insignificance beside that caused by the persecution of hymenopterous insects of the families Ichneumonidae and Pompilidae, especially of the latter, many species of which systematically ransack the country for spiders wherewith to feed their young in the breeding season.

It is no exaggeration to say that countless thousands of spiders of all families are annually destroyed by these insects, and there is no reason to doubt that destruction on at least as great a scale has been going on for centuries, too many even to guess at.

Now the Pompilidae or mason wasps provision their cells with insects of many different kinds, as well as with spiders; but, of the hundreds of species of these wasps that have been described from different parts of the world, only one is known to use ants for this purpose; and this species is not one that preys upon spiders.

So, too, does it appear that ants are entirely immune to the attacks of Ichneumonidae, which destroy hosts of other insects and of spiders by laying their eggs upon their bodies.

As the number of species of insects is believed to exceed that of all other animals taken together, it is no wonder that their study should form a special division of zoology with a distinctive name.

The interest of insects to the eastern races was, however,economic, religious or moral.

During recent years the study of fossil insects (palaeoentomology) has attracted much attention.

Ray's "Insects" comprised the Arachnids, Crustacea, Myriapoda and Annelida, in addition to the Hexapods.

Westwood (Modern Classification of Insects, 1839-1840) connects these older writers with their successors of to-day.

During the pre-Linnaean period, the beauty of insects - especially the Lepidoptera - had attracted a number of collectors; and these "Aurelians" - regarded as harmless lunatics by most of their friends - were the forerunners of the systematic students of later times.

The embryology of insects is entirely a study of the last century.

Kovalevsky in 1871 first described the formation of the germinal layers in insects.

Wallace (both at one time active entomological collectors) contain much evidence drawn from insects in favour of descent with modification.

The Manchurian crane is common, as also are eagles, cuckoos, laughing doves, &c. Insects abound, owing to the swampy nature of much of the country.

Douroucoulis live in parties, and are purely nocturnal, sleeping during the day in hollow trees, and coming out at night to feed on insects and fruits, when they utter piercing cat-like screams.

The flowers show well-marked adaptation to their color and attract insects.

This animal spends most of its time burrowing in the sand in search of insects and their larvae, but occasionally makes its appearance on the surface.

In Sambucus and Viburnum the small white flowers are massed in heads; honey is secreted at the base of the styles and, the tube of the flower being very short, is exposed to the visits of flies and insects with short probosces.

To preserve from insects, the plants, after mounting, are often brushed over with a liquid formed by the solution of lb.

Thus prepared, the specimens are placed on shelves or movable trays, at intervals of about 6 in., in an air-tight cupboard, on the inner side of the door of which, as a special protection against insects, is suspended a muslin bag containing a piece of camphor.

It would seem then that by the stinging of insects or spiders their powers of resistance are overcome and their escape prevented; that some are killed outright and some paralysed is merely an incidental result.

It is limited to Disco Island, and perhaps to a small part of the Noursoak Peninsula, and the neighbouring country, and consists of numerous thin beds of sandstone, shale and coal - the sideritic shale containing immense quantities of leaves, stems, fruit, &c., as well as some insects, and the coal pieces of retinite.

These insects are universally aquatic in their preparatory states.

These gradually become larger, and when so the creature may be said to have entered its "nymph" stage; but there is no condition analogous to the pupa-stage of insects with complete metamorphoses.

Contrary to the habits of all other insects, there yet remains a pellicle that has to be shed, covering every part of the body.

If the observer takes up a suitable position near water, his coat is often seen to be covered with the cast sub-imaginal skins of these insects, which had chosen him as a convenient object upon which to undergo their final change.

Eaton and others have given us valuable works or monographs on the family; but the subject still remains little understood, partly owing to the great difficulty of preserving such delicate insects; and it appears probable they can only be satisfactorily investigated as moist preparations.

Ephemeridae belong to a very ancient type of insects, and fossil imprints of allied forms occur even in the Devonian and Carboniferous formations.

There is much to be said in favour of the view entertained by some entomologists that the structural and developmental characteristics of may-flies are sufficiently peculiar to warrant the formation for them of a special order of insects, for which the names Agnatha, Plectoptera and Ephemeroptera have been proposed.

Pollination is effected by aid of insects.

Some or all of the anthers become twisted so that insects in probing for honey will touch the anthers with one side of their head and the capitate stigma with the other.

Scorpio is here provided with a single or double pair of renal excretory tubes, which have been identified by earlier authors with the Malpighian tubes of the Hexapod and Myriapod insects.

Rabbits, hares, domesticated poultry, game-birds, and, when these run short, rats, mice and even insects, form the chief diet of the fox.

It is stated to live usually in pairs, and to eat rats, birds, frogs, white ants and various insects, and in the north of India it is accused of digging out dead bodies, and several of the native names mean "grave-digger."

Of this smallest of birds there are fifty-nine well-known species, divided into two groups, the Phaethorninae, which prefer the forest shade and live on insects, and the Trochilinae, which frequent open sunny places where flowers are to be found.

Bates, who found 7000 species of insects in the vicinity of only one of his collecting places on the Amazon (Ega), of which 550 species were of butterflies.

Dipterous insects are also very numerous in species, especially in those of sanguinary habits, such as the mosquito, ilium, maroim, carapana, borochudo, &c. In some places these insects constitute a veritable plague, and the infested regions are practically uninhabitable.

Nature has provided several species of animals, birds and reptiles, to feed upon these insects, and various poisonous and suffocating compounds are used to destroy them, but with no great degree of success.

Insects abound in great numbers, the most troublesome and destructive being the tick (Ixodes natalensis), which infests the pasturage, and the white ant (Termes mordax).

The large showy flowers are visited by insects for the honey which is secreted by a ring-like disk below the ovary; large Convolvulus sepium, slightly reduced.

The most important work in this direction has been done by Fritz Muller (Filr Darwin), by Herman Muller (Fertilization of Plants by Insects), Grade b.

The suggestion requires further experimental testing, for which the case of the parthenogenetic production of a portion of the offspring, in such insects as the bee, offers a valuable opportunity for research.

Insects abound, the greatest pest being the tsetse fly, common in the low veld.

Insect life is perhaps poorer and less varied than in Brazil, but in the 14 orders of insects there are no less than 98 families, each including many genera and species.

It is invariably the result of some cause acting generally, such as renal disease, valvular defect of the heart, or an impoverished state of the blood; while a mere oedema is usually dependent upon some local obstruction to the return of blood or lymph, or of both, the presence of parasites within the tissue, such as the filaria sanguinis hominis or trichina spiralis, or the poisonous bites of insects.

Some of the American varieties have been introduced into France and other countries infested with Phylloxera, to serve as stocks on which to graft the better kinds of European vines, because their roots, though perhaps equally subject to the attacks of the insects, do not suffer so much injury from them as the European species.

The Elasmobranchs swallow infected molluscs or fish; pike and trout devour smaller fry; birds pick up sticklebacks, insects and worms which contain Cestode larvae; and man lays himself open to infection by eating the uncooked or partially prepared flesh of many animals.

It tends to destroy insects and weeds, and gets rid of acidity of the soil.

Apart from these characteristics, the most distinctive feature of earwigs is the presence at the end of the abdomen of a pair of pincers which are in reality modified appendages, known as cercopods, and represent the similar limbs of Japyx and the caudal feelers of Campodea and some other insects.

The blackbird feeds chiefly on fruits, worms, the larvae of insects and snails, extracting the last from their shells by dexterously chipping them on stones; and though it is generally regarded as an enemy of the garden, it is probable that the amount of damage by it to the fruit is largely compensated for by its undoubted services as a vermin-killer.

Although it had long been suspected that these insects were in some way connected with malaria and other diseases, while that the species now called Stegomyia calopus was the carrier of yellow fever had been asserted by Finlay as early as 1881, it was not until the closing years of the 19th century that the brilliant researches of Ross in India, and of Grassi and others in Italy, directed the attention of the whole civilized world to mosquitoes as the exclusive agents in the dissemination of malarial fever.

The latter characteristic affords an infallible means for the recognition of these insects, since it at once serves to distinguish them from any blood-sucking flies with which they might otherwise be confused.

Within the area thus defined tsetse-flies are not found continuously, however, but occur only in small tracts called" belts " or " patches," which, since cover and shade are necessities of life to these insects, are always situated in forest, bush or banana plantations, or among other shady vegetation.

Wild animals and tame, carnivorous and graminivorous, insects, birds, fishes and man are adapted to each other."

Indeed, of this porcelain it may be said that, from the monster pieces of blue-and-white manufactured at Setovases six feet high and garden pillar-lamps half as tall again do not dismay the BishU ceramistto tiny coffee-cups decorated in Tokyo, with theil delicate miniatures of birds, flowers, insects, fishes and so forth, everything indicates the death of the old severe aestheticism.

They are viviparous like the Typhlopidae, upon which they feed besides worms and insects.

The insects visit the plant in large numbers, attracted by the foetid smell, and act as carriers of the pollen from one spathe to another.

Hence 'the insects may more conveniently be regarded as constituting the single family Phryganeidae.

Latreille to the primitive wingless insects known as springtails and bristletails.

There young Parkman spent his leisure hours in collecting eggs, insects and reptiles, trapping squirrels and woodchucks, and shooting birds with arrows.

Fertilization is effected by insects, especially by bees, which are directed in their search by the colour and fragrance of the flowers; but some pollen must also be transported by the wind to the female flowers, especially in arctic species which, in spite of the poverty of insect life, set abundant fruit.

The relationship of the Hymenoptera to other orders of insects is discussed in the article Hexapoda, but it may be mentioned here that in structure the highest members of the order are remarkably specialized, and that in the perfection of their instincts they stand at the head of all insects and indeed of all invertebrate animals.

These insects are able, therefore, to bite as well as to suck, whereas most insects which have acquired the power of suction have lost that of biting.

The sucking tongue of the Hymenoptera has often been compared with the hypopharynx of other insects.

The wings in the Hymenoptera show a marked reduction in the number of nervures as compared with more primitive insects.

In the different families of the Hymenoptera, there are various modifications of the ovipositor, in accord with the habits of the insects and the purposes to which the organ is put.

A diggingwasp hunts for insect prey and buries it with the egg, while a true wasp feeds her brood with captured insects, as a bird her fledglings.

Thus we find throughout the order a degree of care for offspring unreached by other insects, and this family-life has, in the best known of the Hymenoptera - ants, wasps and bees - developed into an elaborate social organization.

Thus, wasps catch flies; worker ants make raids and carry off weak insects of many kinds; bees gather nectar from flowers and transform it into honey within their stomachs - largely for the sake of feeding the larvae in the nest.

On the other hand, there are thousands of very small species, and the tiny " fairy-flies " (Myynaridae), whose larvae live as parasites in the eggs of various insects, are excessivel y minute for creatures of such complex organization.

Comparatively only a few species are, for part of their lives, denizens of fresh water; these, as larvae, are parasitic on the eggs or larvae of other aquatic insects, the little hymenopteron, Polynema natans, one of the " fairy-flies " - swims through the water by strokes of her delicate wings in search of a dragon-fly's egg in which to lay her own egg, while the rare Agriotypus dives after the case of a caddis-worm.

No group of terrestrial insects escapes their attacks - even larvae boring in wood are detected by ichneumon flies with excessively long ovipositors.

The Siricidae (" wood-wasps ") are large elongate insects also with one spine on each fore-shin, but with the pronotum closely joined to the mesothorax.

These insects are adorned with bands of black and yellow, or with bright metallic colours, and on account of their large size and formidable ovipositors they often cause needless alarm to persons unfamiliar with their habits.

All the insects included in this group are small and form two families - the Cynipidae and the Figitidae.

The vast majority of this group, including nearly 5000 known species, are usually reckoned as a single family, the Chalcididae, comprising small insects, often of bright metallic colours, whose larvae are parasitic in insects of various orders.

They are among the most minute of all insects and their larvae are probably all parasitic in insects' eggs.

Not a few of these insects, however, are entirely wingless.

On account of their work in destroying plant-eating insects, the ichneumonflies are of great economic importance.

In two of the families - the Mutillidae and Thynnidae - the females are wingless and the larvae live as parasites in the larvae of other insects; the female Mutilla enters humble-bees' nests and lays her eggs in the bee-grubs.

They make burrows wherein they place insects or spiders which they have caught and stung, laying their eggs beside the victim so that the young larvae find themselves in presence of an abundant and appropriate food-supply.

The Sapygidae are parasitic on bees, while the Scoliidae are large, robust and hairy insects, many of which prey upon the grubs of chafers.

The order of the Hemiptera affords, ` therefore, some interesting transition stages towards the complete metamorphosis of the higher insects.

The enormous rate at which aphids multiply under favourable conditions makes them of the greatest economic importance, since the growth of immense numbers of the same kind of plant in close proximity - as in ordinary farm-crops - is especially advantageous to the insects that feed on them.

Several families of bugs are predaceous in habit, attacking other insects - often members of their own order - and sucking their juices.

Others are scavengers feeding on decaying organic matter; the pond skaters, for example, live mostly on the juices of dead floating insects.

The Hemiptera are especially interesting as an order from the variety of aquatic insects included therein.

In many of these insects, while most individuals of the species are wingless, winged specimens are now and then met with.

The occasional development of wings is probably of service to the species in enabling the insects to reach new fresh-water breeding-grounds.

This family of Hemiptera (the Hydrometridae) and the Saldidae contain several insects that are marine, haunting the tidal margin.

The Heteroptera can be traced back farther than any other winged insects if the fossil Protocimex silurica Moberg, from the Ordovician slates of Sweden is rightly regarded as the wing of a bug.

These insects are often found in large numbers on plants whose juices they suck.

The Naucoridae and Belostomatidae are flattened insects, with four-segmented feelers and fore-legs inserted at the front of the prosternum.

Two species of the former family inhabit our islands, but the Belostomatidae are found only in the warmer regions of the globe; some of them, attaining a length of 4 to 5 in., are giants among insects.

The Cicadidae are for the most part large insects with ample wings; they are distinguished from other Homoptera by the front thighs being thickened and toothed beneath.

The young of many of these insects are green and soft-skinned, protecting themselves by the well-known frothy secretion that is called " cuckoo-spit."

These root-dwelling insects are females, which lay parthenogenetic eggs.

If, however, the insect were content with this method of reproduction the disease could be isolated by surrounding the infected patches with a deep ditch full of some such substance as coal-tar, which would prevent the insects spreading on to the roots of healthy vines.

The fertility of the parthenogenetically produced insects would also diminish after a certain number of generations had been produced.

The island is very rich in birds and insects.

Their food is various, consisting of berries, seeds and insects.

The boll-weevil, preying on the cotton, is the most noxious of the insects.

Though his researches were not conducted on any definite scientific plan, his powers of careful observation enabled him to make many interesting discoveries in the minute anatomy of man, the higher animals and insects.

Thus he showed that the weevils of granaries, in his time commonly supposed to be bred from wheat, as well as in it, are grubs hatched from eggs deposited by winged insects.

His chapter on the flea, in which he not only describes its structure, but traces out the whole history of its metamorphoses from its first emergence from the egg, is full of interest - not so much for the exactness of his observations, as for its incidental revelation of the extraordinary ignorance then prevalent in regard to the origin and propagation of "this minute and despised creature," which some asserted to be produced from sand, others from dust, others from the dung of pigeons, and others from urine, but which he showed to be "endowed with as great perfection in its kind as any large animal," and proved to breed in the regular way of winged insects.

Graceful in form and active in motion, sun-birds flit from flower to flower, feeding on small insects which are attracted by the nectar and on the nectar itself; but this is usually done while perched and rarely on the wing as is the habit of humming-birds.

The addition of brilliant ornamentation in shell, teeth, feathers, wings of insects and dyed fibres completed the round of the textile art.

Insects are comparatively few, but ants swarm destructively in the heat of the year.

Both species are omnivorous, feeding voraciously on fruits and insects.

There is a considerable variety of insects, many of them with remarkable peculiarities of structure, and with a predominance of forms incapable of flying.

In animals galls occur mostly on or under the skin of living mammals and birds, and are produced by Acaridea, and by dipterous insects of the genus Oestrus.

They are small insects, having straight antennae, and a compressed, usually very short abdomen with the second or second and third segments greatly developed, and the rest imbricated, and concealing the partially coiled ovipositor.

The dipterous gall-formers include the gall-midges, or gallgnats (Cecidomyidae), minute slender-bodied insects, with bodies usually covered with long hairs, and the wings folded over the back.

Packard, jun., Guide to the Study of Insects, p. 205 (Salem, 1870).

Galls are formed also by hemipterous and homopterous insects of the families Tingidae, Psyllidae, Coccidae and Aphidae.

The escape of the insect takes place on the spontaneous bursting of the walls of the vesicle, probably when, after viviparous (thelytokous) reproduction for several generations, male winged insects are developed.

The galls are gathered before the frosts set in, and are exposed to steam to kill the insects."

Lichtenstein has established the fact that from the egg of the Aphis of Pistachio galls, Anopleura lentisci, is hatched an apterous insect (the gall-founder), which gives birth to young Aphides (emigrants), and that these, having acquired wings, fly to the roots of certain grasses (Bromus sterilis and Hordeum vulgare), and by budding underground give rise to several generations of apterous insects, whence finally comes a winged brood (the pupifera).

Packard, jun., Our Common Insects, p. 203 (Salem, U.S. 1873).

Insects of the State of New York, p. 167 (Albany, 1856).

In many instances the lodgers are not of the same order of insects as the gall-makers.

Again, galls may afford harbour to insects which are not essentially gall-feeders, as in the case of the Curculio beetle Conotrachelius nenuphar, Hbst., of which one brood eats the fleshy part of the plum and peach, and another lives in the " black knot " of the plum-tree, regarded by Walsh as probably a true cecidomyidous gall.

Among the numerous insects parasitic on the inhabitants of galls are hymenopterous flies of the family Proctotrypidae, and of the family Chalcididae, e.g.

A great variety of deformations and growths produced by insects and mites as well as by fungi have been described.

The views of Adler as to the alternation of generations of numerous gall-flies have been fully confirmed, it having been ascertained by direct observation that the galls and the insects produced from them in one generation are entirely different from the next generation; and it has also been rendered certain that frequently one of the alternate generations is parthenogenetic, no males being produced.

Hartig, Die Familien der Blattwespen and Holzwespen (Berlin, 1860); Walsh, " On the Insects, Coleopterous, Hymenopterous and Dipterous, inhabiting the Galls of certain species of Willow," Proc. Ent.

These are very simple, open and generally regular flowers, white, greenish-yellow or yellow in colour and are chiefly visited by insects with a short proboscis, such as short-tongued wasps and flies, also beetles and more rarely bees.

White and yellow colours predominate and insects with a proboscis of medium length are the common pollinating agents, such as short-tongued bees.

Long-tongued insects such as the honey -bee are the most frequent visitors.

Bees, wasps and larger insects serve as pollinating agents FIG.

Despite bad seasons and ravages of insects, cultivation extended, and in 1895 the vineyards covered 300,000 acres, the produce being 88,000,000 gallons.

Ambrosia beetles bore deep though minute galleries into trees and timber, and the wood-dust provides a bed for the growth of the fungus, on which the insects and larvae feed.

Insect life is ricn in northern Melanesia; in southern Melanesia it is less so; in Fiji numerous kinds of insects occur, while individual numbers are small.

But if this is true of the land fauna as a whole, especially on the atolls, where it consists mainly of a few birds, lizards and insects, the opposite is the case with the marine fauna.

Most lizards live on animal food, varying from tiny insects and worms to lizards, snakes, birds and mammals, while others prefer a mixed or an entirely vegetable diet.

Festschrift zum 70ten Geburtstage von Ernst Haeckel, 19(34) has restored the conditions existing in the lagoons and atoll reefs of the Jurassic sea of Solnhofen in Bavaria; he has traced the process of gradual accumulation of the coral mud now constituting the fine lithographic stones in the inter-reef region, and has recognized the periodic laying bare of the mud surfaces thus formed; he has determined the winds which carried the dust particles from the not far distant land and brought the insects from the adjacent Jurassic forests.

It has been discovered that at the beginning of the Eocene the lake of Rilly occupied a vast area east of the present site of Paris; a water-course fell there in cascades, and Munier-Chalinas has reconstructed all the details of that singular locality; plants which loved moist places, such as Marchantia, Asplenium, the covered banks overshadowed by lindens, laurels, magnolias and palms; there also were found the vine and the ivy; mosses (Fontinalis) and Chara sheltered the crayfish (Astacus); insects and even flowers have left their delicate impressions in the travertine which formed the borders of this lake.

Cockerell, including the plants of its shores, the insects which lived upon them, the fluctuations of its level, and many other characteristics of this extinct water body, now in the heart of the arid region of the Rocky Mountains.

These lowland districts are densely forested in the south, except Yucatan, and large areas are covered with streams, swamps and lagoons, the abode of noxious insects, pestilential fevers and dysentery.

These descriptive names are highly poetic, as also that of the Portuguese, " beija-flor " (flower-kisser); but the humming-bird is insectivorous, and thrusts his long bill into flowers in search of insects instead of honey.

To the traveller, the most conspicuous among the Mexican insects, perhaps, are the butterflies, beetles, ants and the myriads of mosquitoes, midges, fleas and chinches.

These insects are blind and avoid the light.

In Yucatan the open plains, rich pasture, and comparative freedom from moist heat, insects and vampire bats, have been particularly favourable to cattle-raising, and the animals are generally rated among the best in Mexico.

Such a state of affairs is produced by the march of civilization into the " hinterlands " of the various colonies, when man, together with the numerous domesticated animals which accompany him, is brought into proximity to big game, &c., and, what is equally important, into the zone of the particular blood-sucking insects which prey upon the same.

It is, for instance, quite likely that certain Herpetomonadine parasites described by Leger (2 9, 34) from various blood-sucking insects are really only stages in the life of a Haemoflagellate.

It flourishes best in small tanks and ponds, in which the water is constantly changing and does not freeze; in such localities, and with a full supply of food, which consists of weeds, crumbs of bread, bran, worms, small crustaceans and insects, it attains to a length of from 6 to 12 in., breeding readily, sometimes at different times of the same year.

These animals live in the forests of the Malay Peninsula, Sumatra, Borneo and the Philippine Islands, where they feed chiefly on leaves, and probably also on insects.

So, also, are the first relics of insects.

So also had insects and some other forms, of land life.

In spring the chaffinch is destructive to early flowers, and to young radishes and turnips just as they appear above the surface; in summer, however, it feeds principally on insects and their larvae, while in autumn and winter its food consists of grain and other seeds.

But detailed study of these various groups of insects shows that beneath their common superficial resemblances lie important distinctions in structure, and essential differences in the course of the life-history.

The dragon-flies and May-flies are also active throughout their lives and possess external wingrudiments, though the young insects differ rather strikingly from their parents.

But if classification is to express relationship, it is impossible to associate in the same order families whose kinship to insects of other orders is nearer than their kinship to each other.

And no student can doubt that the stone-flies are akin to Orthoptera and the caddis-flies to the Lepidoptera, while dragon-flies and May-flies stand in an isolated position with regard to all other insects.

In the present article, for the sake of convenience, all the insects which have been regarded by Linnaeus and others as "Neuroptera " are included, but they are distributed into the orders agreed upon by the majority of modern observers, and short characters of these orders and their principal families are given.

Both head and trunk are somewhat flattened dorso-ventrally, giving the insects a very distinct and characteristic aspect.

The perfect insects, whose flight is feeble, are never found far from the water.

The Embiidae are feeble, somewhat soft-skinned insects with the prothorax small and the mesothorax and metathorax elongate.

They are relatively shorter and broader insects than the Embiidae with large prothorax and long wings, which have a transverse line of weakness at the base and are usually shed after the nuptial flight.

The insects included in this order differ from those of the two preceding orders in their more condensed abdomens which bear no cerci, while the number of Malpighian tubes is reduced to four.

Burmeister (1832) and has reference to the biting habits of the insects.

The feelers of these insects are elongate and thread-like, consisting of from a dozen to nearly thirty segments.

The book-lice are familiar wingless insects, often found in houses running about among old papers and neglected biological collections.

Hagen observed that some genera possess wing-like outgrowths on the prothorax, comparable to those seen in certain insects of the Carboniferous Period.

They resemble the May-flies in their " hemimetabolous " lifehistory; the young insects are markedly unlike their parents, inhabiting fresh water and breathing dissolved air, either through tracheal gills at the tip of the abdomen, or by a branching system of air-tubes on the walls of the rectum into which water is periodically admitted.

The winged insects resemble the May-flies in their short feelers and in the large number (50 to 60) of their Malpighian tubes, but differ most strikingly from those insects in their strong wellarmoured bodies, their powerful jaws adapted for a predaceous manner of life, and the close similarity of the hind-wings to the forewings.

The insects retained in the order Neuroptera as restricted by modern systematists are distinguished from the preceding orders by the presence of a resting pupal stage in the life-history, so that a " complete metamorphosis " is undergone.

The larvae are active and well-armoured, upon the whole of the ' ` campodeiform " type, but destitute of cerci; they are predaceous in habit, usually with slender, sickle-shaped mandibles, wherewith they pierce various insects so as to suck their juices.

Some American genera (Corydalis) which belong to this family are gigantic among insects and their males possess enormous mandibles.

The Myrmeleonidae are large insects with short clubbed feelers on their prominent heads, and two pairs of closely similar net-veined wings, with regular oblong areolets at the tips.