The generic name of Trypanosoma was conferred by Gruby in 1843 upon the wellknown parasite of frogs.
Sheep, how ever, suffer most from this parasite and from the allied D.
There it feeds first as an internal parasite of the waspgrub, then bores its way out, moults and devours the wasp larva from outside.
Perhaps the converse is more feasible in some circumstances - that is to say, preventing mosquitoes from having access to malarial persons, and so propagating the parasite in themsevles.
The parasitic hypothesis postulates the invasion of a parasite from without, thus making a new growth an infective process.
palpalis, of Equatorial Africa, whose bite transmits the human parasite (T.
Adaptive characters are often hereditary, for instance, the seed of a parasite will produce a parasite, and the same is true of a carnivorous plant.
The American parasite described by Stiles, and called Uncinaria americana (whence the name Uncinariasis for this disease) differs slightly from the Ankylostoma.
The existence of the parasite is maintained by a vicious interchange between its alternate hosts, mosquitoes and man,.
Before the end of the 19th century this discovery of the blood parasite of malaria was crowned by the hypothesis of Patrick Manson, proved by Ronald Ross, that malaria is propagated by a certain genus of gnat, which acts as an intermediate host of the parasite.
If the cycle be broken at any point the parasite must die out, assuming that it has no other origin or mode of existence.
The male, however, is a veritable pigmy beside the female, and during copulation presents the appearance of a parasite attached to her abdomen.
In the case of oxen the alternate host of the parasite is a special tick (Smith and Kilborne).
For some of these, as redwater (pyrosoma), antidotes are already found; for others, as for Texas fever - of which the parasite is unknown, but the mode of its transmission, by the mosquito, discovered (Finlay-Reed) - preventive measures are reducing the prevalence.
Thus we get a complete scientific demonstration of the causation of malaria in three stages: (1) the discovery of the parasite by Laveran; (2) its life-history in the human host and connexion with the fever demonstrated by the Italian observers; (3) its life-history in the alternate host, and the identification of the latter with a particular species of mosquito by Ross and Manson.
The itch-insect (Sarcoptes scabiei) is a well-known human parasite, so minute that it was not discovered until the end of the 18th century, and " the itch " was treated medicinally as a rash.
In 1898 it was conclusively shown in Italy that if a mosquito E of the Anopheles variety bites a person suffering from malaria, and is kept long enough for the parasite to develop in the salivary gland, and is then allowed to bite a healthy person, the latter will in due time develop malaria.
6) has a good deal to tell about the viscum, a deadly parasite, though slower in its action than ivy.
In the case of filariasis due to Filaria bancrofti, which is common throughout the Tropics, the embryos of the parasite are disseminated by various Culicinae and Anophelinae (Culex pipiens in Queensland; C. fatigans in the West Indies; Myzomyia rossii in India; Pyretophorus costalis in a large portion of tropical Africa; &c.).
In scabies (itch) it is the best remedy, killing the male parasite, which remains on the surface of the skin.
The discovery of the parasite of malaria by Laveran, and of the method by which it gains entrance to the human body, through the bite of a particular variety of mosquito, by Manson and Ross, promises much in the way of eradication of the disease in the future.
If the attack of a parasite is met by the formation of some substance in the protoplasm which is chemo- tactically repulsive to the invader, it may be totally incapable of penetrating the cell, even though equipped with a whole armoury of cytases, diastatic and other enzymes, and poisons which would easily overcome the more passive resistances offered by mere cell-walls and cell-contents of other plants, the protoplasm of which forms bodies chemotactically attractive to the Fungus.
1845) discovered the parasite of malaria, and truly conceived its relations to the disease; thus within two years were made two discoveries either of which was sufficient to make the honour of a century.
demonstrated by a series of accurate investigations, contributed by many workers, that malaria is caused by a microscopic parasite in the blood, into which it is introduced by the bites of certain species of mosquito.
The larvae of this parasite develop in the Malpighian tubules of the insect; at a certain stage they cast their cuticle and make their way into the space - part of the haemocoel - found in the labium.
If such a general parasite carries its activities farther, every cell may be killed and the plant forthwith destroyed e.g.
The origin of the parasite and its mode of introduction into the blood remained to be discovered.
In 1894 (Sir) David Bruce discovered the celebrated South African parasite (T.
brucii, the nagana parasite in G.
It has been shown that this parasite feeds upon the blood, not the bile of its host, though it occurs mainly in the bile ducts.
It is now held that the parasite enters the blood of man through the piercing mouth-parts at the time of biting.
In dealing with disease-causing forms, the more narrowly the original source of the parasite concerned is defined, the closer do we get to the true vertebrate host or hosts.
It is probable that the parasite is then transferred to the alimentary canal of man by means of drinking-water, and thence makes its way to the subcutaneous connective tissue.
It must not be overlooked that the living cells of the plant react upon the parasite as well as to all external agencies, and the nature of disease becomes intelligible only if we bear in mind that it consists in such altered metabolismdeflected physiologyas is here implied.
The old age of Trembecki appears to have been ignoble and neglected; he had indeed "fallen upon evil days and evil tongues"; and when he died at an advanced age all the gay courtiers of whom he had been the parasite were either dead or had submitted to the Muscovite yoke.
It is important to note that although sleeping sickness (of which the chief foci are at present the Congo Free State and Uganda) has hitherto been associated with one particular species of Glossina, it has been shown experi mentally both that other tsetse-flies are able to transmit the parasite of the disease, and that G.
By this time the embryo has all the organs of the adult perfected save only the reproductive; these develop only when the first host is swallowed by the second or final host, in which case the parasite attaches itself to the wall of the alimentary canal and becomes adult.
18, Bureau of Plant Industry, U.S. Department of Agriculture), who attributes it not to any specific parasite but to a disturbance of the normal physiological activity of the cells.
In the treatment of a case where the parasite is already present, for two days previous to the employment of a vermifuge a light diet should be given and the bowels moved by a purgative.
The parasite effects a lodgment in the host either by invading it as a free-swimming planula, or, apparently, in other cases, as a spore-embryo which is captured and swallowed as food by the host.
It is one thing to protect individuals from mosquito bites, another to prevent the propagation of the parasite in a whole community.
The animal cell can absorb its carbohydrate and proteid food only in the form of carbohydrate and proteid; it is dependent, in fact, on the pre-existence of these organic substances, themselves the products of living matter, and in this respect the animal is essentially a parasite on existing animal and plant life.
The human flea is considerably exceeded in size by certain other species found upon much smaller hosts; thus the European Hystrichopsylla talpae, a parasite of the mole, shrew and other small mammals, attains a length of 5z millimetres; another large species infests the Indian porcupine.
The female is viviparous, and the young, which, unlike the parent, are provided with a long tail, live free in water; it was formerly believed from the frequency with which the legs and feet were attacked by this parasite that the embryo entered the skin directly from the water, but it has been shown by Fedschenko, and confirmed by Manson, Leiper and others, that the larva bores its way into the body of a Cyclops and there undergoes further development.
Numerous wild hypotheses as to changes in the constitution of the host-plant, leading to supposed vulnerability previously non-existent, would probably never have seen the light had the full significance of the truth been grasped that an epidemic results when the external laciors favor a parasite somewhat more than they do the host.
Speaking generally each species of parasite has a particular host, upon the blood of which it nourishes itself and matures its reproductive organs.
The labours of Golgi, Marchiafava, Celli and others established the nature of the parasite and its behaviour in the blood; they proved the fact, guessed by Rasori so far back as 1846, that the periodical febrile paroxysm corresponds with the development of the organisms; and they showed that the different forms of malarial fever have their distinct parasites, and consequently fall into distinct groups,.
Section through union between parasite and host.
The attention of birds is speedily attracted to the snail by this appearance and by the peculiar movements which the worm executes, and the passage of the parasite into its final host is advantageously effected.
Demodex folliculorum is also a common parasite of the sebaceous glands of the skin of the face in man, and is frequent in the skin of the dog.
in which definite stages of the parasite's life-cycle are undergone.
In the case of the pearl oyster this parasite is a cestode larva, but in the less valuable but no less genuine pearl produced by Mytilus, &c., the nucleus is a Trematode-larva (Jameson).
The blood of most species behaves differentially towards precipitants, and it is therefore conceivable that when blood is used as food and is elaborated into special compounds for the nutrition of the reproductive organs of a parasite, these specific or larger differences in the blood of animal hosts may prevent the ripening of the gonads of a widely diffused parasite and only one particular kind of blood prove suitable.
This parasite is one of the plagues (From Cambridge Natural History, vol.
All the members of this order are parasitic on aquatic vertebrates and in rare cases derive their food from a vertebrate host indirectly by means of another invertebrate parasite (e.g.
It shows how a bold and p lausible adventurer, aided by the profligacy of a parasite, the avarice and hypocrisy of a confessor, and a mother's complaisant familiarity with vice, achieves the triumph of making a gulled husband bring his own unwilling but too yielding wife to shame.
Schaudinn has stated, however, that Trypanomorpha becomes, in certain phases, attached to a red blood-corpuscle (ectoglobular), and, in others, penetrates inside one and eventually destroys it (endoglobular); while his other avian parasite, Trypanosoma ziemanni, apparently draws up into itself the white corpuscle (leucocyte) to which it becomes attached.
sanguinis, Gruby, November 1843, Undulina ranarum, Lank., 1871), the best-known parasite of frogs, which exhibits remarkable polymorphism (fig.
and Mesnil, a very long vermiform parasite, from eels (fig.
a, Typical pear-shaped or oval forms; b, various stages in longitudinal division; c, nuclear division preparatory to multiple fission; d, endoglobular forms, in red blood-corpuscles (p = pigment grains); e, bacillary form of the parasite in a corpuscle; M, large macrophageal cell with many parasites (after Donovan).
Sergent, " Sur un trypanosome nouveau parasite de la grenouille verte," C. r.
SCABIES, or Itch, a skin disease due to an animal parasite, the Sarcoptes scabei (see Mite), which burrows under the epidermis at any part of the body, but hardly ever in the face or scalp of adults; it usually begins at the clefts of the fingers, where its presence may be inferred from several scattered pimples, which will probably have been torn at their summits by the scratching of the patient, or have been otherwise converted into vesicles or pustules.
Parasitism: " On some Relations between Host and Parasite," Proc. Roy.
The unexpected occurrence of these worms in pools and puddles, often in great numbers, has given rise to myths about showers of worms. They occasionally make their way into the human stomach with the drinking-water and are vomited; but this is a case of pseudo-parasitism - they are no true parasite of man.
Both of these schizont stages release numerous merozoites, capable of infecting erythrocytes and generating the bloodstream forms of the parasite.
Use commercially frozen barbecue foods as the freezing process kills the toxoplasmosis parasite and always make sure food is cooked right through.
Toxoplasmosis Toxoplasmosis gondii is a protozoa parasite that may causes infection in the brain.
Caused by the trypanosome parasite Trypanosoma brucei rhodesiense, which is carried by the tsetse fly, the disease is fatal if not treated.
The word is thus transferred, in biology, to an animal or plant upon which a parasite lives.
The term parasite, from meaning a "hanger-on," has been transferred to any living creature which lives on another one.
When thousands after thousands are dragooned out of their country for the sake of their religion, or sent to row in the galleys for selling salt against law, - when the liberty of every individual is at the mercy of every prostitute, pimp or parasite that has access to power or any of its basest substitutes, - my mind, I own, is not at once prepared to be satisfied with gentle palliatives for such disorders" (Francis to Burke, November 3, 1790).
All vitality had been sapped from the old order of nobles, reduced in prestige by the savonnette a vilains (office purchased to ennoble the holder), enervated by court life, and so robbed of its roots in the soil, from which it had once drawn its strength, that it could no longer live save as a ruinous parasite on the central monarchy.
Sir Peter (D): Sir Harry (D), Archduke (D), Ditto (D), Paris (D), Hermione (0), Parasite (0), Ambrosio (L), Fyldener (L), Paulina (L), Petronius (L).
Now, since it seems this Manatus senegalensis ascends rivers, we may infer that its parasite travels with it.
To the extreme development of the carapace in Laura, as compared with the segmented body, it would be difficult to find among crustaceans any analogy more striking than that of the great ovarial expansions in Nicothoe astaci, the little copepod parasite of the common lobster.
He emptied two water bottles before 10:00 and replenished them in one of the ice-cold streams, too thirsty to heed the literature of a possible parasite from elk urine or something.
The suckers are approximately the same in size, the ventral sucker being slightly anterior to the midline of the parasite.
In order to cause the disease, the single-celled parasite must multiply in the human bloodstream.
Malaria parasite antigens exposed on the surface of the infected red blood cell membrane.
The co-existence of the asexual encysted form and the sexually mature adult in the same host, exceptionally found in 011ulanus and other Nematodes, is the rule in Trichinella; many of the embryos, however, are extruded with the faeces, and complete the life cycle by reaching the alimentary canal of rats and swine which frequently devour human ordure Swine become infested with Trichinella in this way and also by eating the dead bodies of rats, and the parasite is conveyed to the body of man along with the flesh of "trichinized" swine.
If it were as simple as hair loss caused by a parasite, you would likely see her scratching and biting at the affected area, but from what you've told me this doesn't seem to be the case.
Is it possible that she has picked up a flea or parasite?
This parasite is thought to be carried by fleas and ticks.
While fish should not be served raw because of potential parasite infestation, it can be served lightly cooked.
Her second film was the science fiction thriller Parasite.
Dogs who contract this parasite suffer significant illness and can even die.
Cases of this parasite have now been reported throughout the United States, and the parasite can affect all Dog Breeds.
Because of this, dog owners who travel frequently should take all preventative measures to protect their pets even if there is no indication of a parasite's presence.
Supplementary treatment may also be necessary to help repair the parasite's damage to the heart and lungs, and the animal may be susceptible to pulmonary infections for some time afterwards.
Ask the vet for advice on parasite prevention.
These alternative treatments for heartworm prevention include Petalive Parasite Dr. and Heartworm Free.
Herbal treatments, such as HeartWorm Free and PetAlive Parasite Dr., are said to not only prevent against heartworms but also improve an animal's overall health.
Mistletoe (Viscum Album) - This on trees is often welcome in the pleasure ground or orchard, and is not without beauty of color, but where abundant it is injurious, being a true parasite which thrives at the expense of its victim.
In the case of a natural pearl the irritant may be a grain of sand, a parasite or tiny pebble.
The disease is caused by a parasite called Trypanosome brucei.
A bite from a tsetse fly is all that's needed to transmit the protozoa, but the parasite's life cycle in a person is very distinct.
The parasite has entered the central nervous system by crossing over the blood to brain barrier.
The problem here is that the drug also needs to be able to cross the blood to brain barrier in order to reach the parasite and kill it.
Parasite Eve isn't a rare game, most used shops probably carry it.
Toxoplasmosis is caused by Toxoplasma gondii, a parasite that can be acquired by the mother from handling cat feces, drinking unpasteurized milk, or eating contaminated meat.
Any suspected infection should be reported to the obstetrician so that testing for the causative parasite in the mother can be performed.
The virus is usually a harmless parasite of human beings.
Toxoplasmosis is caused by a one-celled parasite Toxoplasma gondii.
There is evidence that a protozoan parasite (Dientamoeba fragilis) is transmitted among humans in the eggs of pinworms.
Humans are most commonly infected by swallowing the oocyte form of the parasite in soil (or kitty litter) contaminated by feces from an infected cat; or by swallowing the cyst form of the parasite in raw or undercooked meat.
Some people become convinced that their itch is caused by a parasite; this conviction is often linked to burning sensations in the tongue and may be caused by a major psychiatric disorder.
Carrier state-The continued presence of an organism (bacteria, virus, or parasite) in the body that does not cause symptoms, but is able to be transmitted and infect other persons.
Traveler's diarrhea-An illness due to infection from a bacteria or parasite that occurs in persons traveling to areas where there is a high frequency of the illness.
Up to 10 percent of pregnant women harbor the chlamydial parasite.
The signs and symptoms of adult inclusion conjunctivitis appear two to 19 days after contact with an individual who harbors the chlamydia parasite.
Classically considered a parasite, it appears to be more related to fungi.
The eosinophil is a component of the immune system and is particularly involved with defense against parasites, but as of 2004 no parasite had been found responsible for any of the eosinophilic gastroenteropathies.
Iron deficiency caused by hookworm infection requires drug therapy to eliminate the parasite; prevention includes wearing shoes when walking in soil known to be infested with hookworms.
Pneumocystis carinii-A parasite transitional between a fungus and protozoan, frequently occurring as aggregate forms existing within rounded cystlike structures.
Mite-An insect parasite belonging to the order Acarina.
Fresh fruits and vegetables can be contaminated with a parasite called Toxoplasma gondii.
This disease is caused by a microscopic parasite called Ichthyophthirius multifiliis, and it resembles small, white dots along the body of the fish.
If your goldfish has a velvety-orange coating on its body or on its fins, then it is probably suffering from Velvet disease, which cause by a parasite called Oodinium pillularis.
Chilodonella is similar to ick, but much more dangerous because it is not readily noticeable until the parasite has already caused severe tissue damage.
Hole in the head disease is not as common in golfish, but it is mainly caused by poor water quality that allows protozoan parasite and bacteria to flourish.
This will cause the goldfish to rub up against the tank or objects inside the tank in an effort to dislodge the parasite.
These are the anti-spyware windows that appear telling you that your system has been infected and asks the user to click on a button to clean the offensive parasite off his computer.
Bedbug bites are often the first clue of a parasite infestation.
gambiense, the human parasite (fig.
PARASITE (From Gr.
Failure to detect cues from the immune system changes the parasite's development pattern.
Using LCMS techniques, we have already proven that chalcone release takes place in the parasite digestive vacuole.
Amebic dysentery is caused by the protozoan parasite Entamoeba histolytica.
leaving sites fallow will reduce the risk of disease or parasite transmission.
Can anyone give me the name of the disease caused by a parasite from a dogs feces, or the name of the parasite?
gastroenteritis caused by the parasite Cryptosporidium which lives in the bowel.
genus in a new survey of species from 335 genera of higher plants, 48 were found to have the parasite.
This parasite must be considered one of the most pathogenic of the parasitic helminths.
In addition, a number of specimens of other important parasite helminths are also displayed on the center bench.
helminth immunology and the interaction of multiple parasite species on other infectious diseases.
Currently I am on the editorial board of parasite immunology to give statistical advice to submitted papers.
infected by the parasite, it's a messy thrill-ride of increasingly grotesque adventures.
interfere with DNA replication within the malarial parasite.
listeria bacteria and the toxoplasmosis parasite.
A significant proportion of the adult human population has been infected by the parasite, depending on lifestyle and geographic locale.
malaria parasite antigens exposed on the surface of the infected red blood cell membrane.
malaria parasite plasmodium falciparum.
These drugs induce necrosis of the parasite but also produce unwanted side-effects in treated animals.
He is a Venetian nobleman and Mosca regards himself as a better class of ' parasite ' altogether.
nucleoside transporters at the parasite's plasma membrane is associated with resistance.
obligate parasite ' .
From the moment Michael Rooker's town bully becomes infected by the parasite, it's a messy thrill-ride of increasingly grotesque adventures.
parasite Plasmodium falciparum.
It also allows the squirrel to reduce the level of parasite infestation they suffer by leaving parasite infestation they suffer by leaving parasites behind in the nest.
parasite virulence is a powerful concept that dynamically changes in natural systems when necessary.
parasite Cryptosporidium which lives in the bowel.
Shared nematode parasite is developing in Pheasant much better than in Partridge, but has much greater effect on the later.
phylogenyT and PARASITE blocks describe the host and parasite phylogenies.
Error in phylogeny will be illustrated with a comparison of two contemporary primate or host phylogenies against the pinworm or parasite phylogeny.
Malaria is an infectious disease due to the presence of a parasite called plasmodium within the red blood cells.
plasmodium parasite infecting the red blood cells.
They describe the life cycle of the mosquito parasite plasmodium.
The effect of parasite dose on severity of disease in the rodent malaria plasmodium chabaudi.
They frequently develop foot and hoof problems, are malnourished, become parasite ridden and wear poorly fitting harnesses.
schizont stages release numerous merozoites, capable of infecting erythrocytes and generating the bloodstream forms of the parasite.
The parasite that causes sleeping sickness is called the trypanosome.
Parasite infectivity to hybridizing host species: a link between hybrid resistance and allopolyploid speciation?
Eggs are therefore actively deposited by the parasite, in contrast to the disintegration of the proglottids seen in the other human tapeworms.
toxoplasmosis parasite and always make sure food is cooked right through.
Toxoplasmosis toxoplasmosis Toxoplasmosis gondii is a protozoa parasite that may causes infection in the brain.
Aimed at the public, this brochure describes bovine trichomoniasis, a venereal disease of cattle caused by the parasite Tritrichomonas fetus.
trypanosome parasite Trypanosoma brucei rhodesiense, which is carried by the tsetse fly, the disease is fatal if not treated.
ventral sucker being slightly anterior to the midline of the parasite.
Frank, S. A. (1996) Models of parasite virulence.
The tiny wasps are also a parasite to many kinds of caterpillars.
For example, in countries where filarial worms were once very common, lots of people were dying of the parasite infections.
Manson and Bancroft suggested that the second host of the parasite is the mosquito or gnat, and for a long time it was thought that they were conveyed to man by the mosquito dying after laying her eggs in water, the larval nematodes escaping from her body and being swallowed by man.
Parasitism, &c. Marshall Ward, On some Relations between Host and Parasite, &c., Proc. Roy.
In 1894, however, Sir Patrick Manson, arguing with greater precision by analogy from his own discovery of the cause of filariasis and the part played by mosquitoes, suggested that the malarial parasite had a similar intermediate host outside the human body, and that a suctorial insect, which would probably be found to be a particular mosquito, was required for its development.
The phytophagous species are attached to various parts of plants, dead or alive; and the carnivorous in like manner feed on dead or living flesh, or its products, many larvae being parasitic on living animals of various classes (in Australia the larva of a species of Muscidae is even a parasite of frogs), especially the caterpillars of Lepidoptera, which are destroyed in great numbers by Tachininae.
Inaugurated by Pasteur's early work, progress in this subject was first marked by the discovery of the parasite of anthrax and of those organisms productive of fowl-cholera and septic disease.
Man himself, as well as other mammals, is the intermediate host of the dangerous parasite, Taenia echinococcus, in countries where cleanliness is neglected; the pig is the host of Taenia solium, and other cases may be seen from the table at the end of this article.
The head must be carefully searched for by the physician, as should it fail to be brought away the parasite continues to grow, and within a few months the segments again begin to appear.
Sharing your intimate and restful space with a parasite is an unsettling reality.
The alleged occurrence of the disease in localities free from mosquitoes or without their agency is not well attested; its absence from other localities where they abound is accounted for by their being of an innocent species, or - as in England - free from the parasite.
It is believed that all of them may serve as hosts of the parasite.
There remains the question of protection against the parasite.
This immunity is apparently not due to the absence of favourable conditions, but rather to the presence of some inimical factor which prevents the development of the parasite.
Much of the grain was never harvested, whilst owing mainly to the excessive floods there commenced an outbreak of liver-rot in sheep, due to the ravages of the fluke parasite.
Sheep-scab is a loathsome skin disease due to an acarian parasite.
Cell in a state of degeneration and chromatolysis; the large rounded body in the cell is a cancer parasite.
This depends largely on the station adopted by the parasite.
The knowledge of the presence of the parasite adversely affects nervous people and may lead to mental depression and hypochondria.
The production of pearls by oysters and mussels is common knowledge, but it is only recently that the origin of pearls has been traced and admitted to be due to inflammation set up by a parasite.
Not a few cases are known in which a parasitic larva is itself pierced by the ovipositor of a " hyperparasite," and even the offspring of the latter may itself fall a victim to the attack of a " tertiary parasite."
3, E), which is to be derived from a Herpetomonadine type, the single, anterior flagellum of the ancestral parasite has been drawn backwards along one side of the body and now originates in the posterior half.
Probably this is not a haemal parasite, and lacks an alternate host.
The splenic type is somewhat smaller than Wright's parasite; the former, when pear-shaped, is from 31 to 4 p..
Siedlecki have published an important account (17) of this parasite, which they consider possesses a true trypaniform phase, and for which they have proposed the name Trypanosoma luis.
i and 2; (7) S.R.Christophers,"Reports on a parasite found in persons suffering from enlargement of the spleen in India," Sci.
et Mesn.) parasite d'une fievre de 1'Inde, " C. r.
Leger, " Sur un flagelle parasite de l' Anopheles maculipennis," C. r.
sp., parasite du sang de Cobitis barbatula, L."
Gregory Nazianzen tells us that his father was a fuller, and that he himself soon became notorious as a parasite of so mean a type that he would "sell himself for a cake."
An epiphytic fungus is not necessarily a parasite, however, as many saprophytes (moulds, &c.) germinate and develop a loose mycelium on living leaves, but only enter and destroy the tissues after the leaf has fallen; in some cases, however, these saprophytic epiphytes can do harm by intercepting light and air from the leaf (Fumago, &c.), and such cases make it difficult to draw the line between saprophytism and parasitism.
Similar gradations are observed in the direct effect of the parasite on the host, which may be local (Hemileia) when the mycelium never extends far from the point of infection, or general (Phytophthora) when it runs throughout the plant.
A parasite may be restricted during a long incubation-period, however, and rampant and destructive later (Ustilago).
The latter fact, as well as the extraordinary fastidiousness, so to speak, of parasites in their choice of hosts or of organs for attack, point to reactions on the part of the host-plant, as well as capacities on that of the parasite, which may be partly explained in the light of what we 'now know regarding enzymes and chemotropism.
Some parasites attack many hosts and almost any tissue or organ (Botrytis cinerea), others are restricted to one family (Cystopus candidus) or genus (Phytophthora infestans) or even species (Pucciniastrum Padi), and it is customary to speak of rootparasites, leaf-parasites, &c., in expression of the fact that a given parasite occurs only on such organs - e.g.
The surface of the skin may be invaded by parasitic organisms and may exhibit spots, which are removed by something which will destroy the parasite, such as ointments containing mercurial salts.
The second class dealt with different classes of the population (the sailor, the prophet, the boor, the parasite).
The parasite, which has a somewhat restricted range of host plants, chiefly invades the potato, Solanum tuberosum; the bittersweet, S.
The highest powers are required to see all parts of the parasite.
The parasite may be held in check by spraying with Bordeaux mixture early in the season.
In the parasitic Copepoda and Isopoda the disparity in size is carried to an extreme degree, and the minute male is attached, like a parasite, to the enormously larger female.
The most common human parasite is the Ascaris lumbricoides or round worm, found chiefly in children and occupying the upper portion of the intestine.
The threadworm or Oxyuris vermicularis is a common parasite infecting the rectum.
In this society, where there was no traffic in anything but wealth and ideas, the soldier was nothing more than an agitator or a parasite.
The eggs are laid in the nests of various bees and wasps, the chrysid larva living as a " cuckoo " parasite.
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