This area is termed the "conducting" area, as distinguished from the lower or "detentive" gland-bearing area.
Other glands opening on or near the foot are: (I) The suprapedal gland opening in the middle line between the snout and the anterior border of the foot.
They have a musk gland on top of their rump that produces a smell when they get upset.
A, Honey-gland from attractive C, Transverse section of the surface of lid.
Two pairs of salivary ducts, each leading from a salivary gland, open into the buccal chamber.
The gland has been found in both sub-orders of the Pectinibranchia, in Cyclostoma and Cypraea among the Taenioglossa, in Hemifusus, Cassis, Nassa, Murex, Fasciolariidae, Turbinellidae, Olividae, Marginellidae and Conidae among the Stenoglossa.
This c and common cross fertilization is often effected by the gland g.
It is the adrectal gland, and in the genera Murex and Purpura secretes a colourless liquid which turns purple upon exposure to the atmosphere, and was used by the ancients as a dye.
The preconchylian invagination or shell-gland is formed in the embryo behind the velum, on the surface opposite the blastopore.
This is the so-called c narion, or pineal gland, where in a minimized point the mind on one hand and the vital spirits on the other meet and communicate.
But, on the other hand, the vital spirits cause a movement in the gland by which the mind perceives the affection of the organs, learns that something is to be loved or hated, admired or shunned.
The tail is long and in some cases prehensile; the first hind-toe may be either large, small or absent; the dentition usually includes three pairs of upper and one of lower incisors, and six or seven pairs of cheekteeth in each jaw; the stomach is either simple or sadculated, without a cardiac gland; and there are four teats.
B, Digestive gland from interior A, B, and C magnified about of pitcher, in pocket-like deI oo diameters.
The pneumato phore arises from the ectoderm as a pit or invagination, part of which forms a gas-secreting gland, while the rest gives rise to an air-sack lined by a chitinous cuticle.
In addition to these lines, all tadpoles show more or less distinctly a small whitish gland in the middle of the head between the eyes, the so-called frontal gland or pineal gland, which in early stages is connected with the brain.
It is, however, fair to state that his system was not built entirely upon these muscular variations, but rather upon a more laborious combination of anatomical characters, which were so selected that they presumably could not stand in direct correlation with each other, notably the oil-gland, caeca, carotids, nasal bones and above all, the muscles of the thigh.
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.
In the latter a pallial siphon, a welldeveloped proboscis and an unpaired oesophageal gland are always present, in the former they are usually absent.
The enlarged glandular structure of the walls of the rectum is frequent in the Pectinibranchia, as is also though not universal the gland marked y, next to the rectum.
This is clearly the same process in essence as that of the formation of a vitellogenous gland from part of the primitive ovary, or of the feeding of an ovarian egg by the absorption of neighbouring potential eggs; but here the period at which the sacrifice of one egg to another takes place is somewhat late.
A gland and tuft are present on the skin of the outer side of the upper part of the hind cannon-bone; but, unlike American deer, there is no gland on the inner side of the hock.
In that gland the mystery of creation is concentrated; thought meets extension and directs it; extension moves towards thought and is perceived.
Haeckel regards it as the equivalent of the manubrium, and as it is implanted on the blind end of the pneumatophore, such a view leads necessarily to the air-sack and gland being a development on the ex-umbral surface of the medusa-person.
Moreover, the pollen, instead of consisting of separate cells or grains, consists of cells aggregated into "pollen-masses," the number varying in different genera, but very generally two, four, or eight, and in many of the genera provided at the base with a strap-shaped stalk or "caudicle" ending in a flattish gland or "viscid disk" like a boy's sucker.
This column stands up from the base of the flower, almost at right angles to the lip, and it bears at the top an anther, in the two hollow lobes of which are concealed the two pollen-masses, each with its caudicle terminating below in a roundish gland, concealed at first in the pouch-like rostellum at the front of the column.
The essential feature of the asymmetry of Gastropoda is the atrophy or disappearance of the primitively left half of the circumanal complex (the right half in sinistral forms), including the gill, the auricle, the osphradium, the hypobranchial gland and the kidney.
This organ is probably homologous with the byssogenous gland of Lamellibranchs.
Cunningham that in Buccinum the egg-capsules are formed by this pedal gland and not by any accessory organ of the generative system.
B, Sole of the foot of Pyrula tuba, to show a, the pore usually said to be " aquiferous " but probably the orifice of a gland; b, median line of foot.
Forms and in terrestrial genera such as Cyclostoma; (2) the anterior pedal gland opening into the anterior groove of the foot, generally present in aquatic species; (3) dorsal posterior mucous glands in certain Cyclostomatidae.
In forms which are naked in the adult state, the shell falls off soon after the reduction of the velum, but in Cenia, Runcina and Vaginula the shell-gland and shell are not developed, and the young animal when hatched has already the naked form of the adult.
To the right of Spengel's osphradium is the opening of a peculiar gland which has, when dissected out, the form of a bunch of grapes; its secretion is said to be poisonous.
In the hinder part of the foot (not shown in any of the diagrams) is the opening of a large mucusforming gland very often found in the Molluscan foot.
On examination this is found to be the under surface of the posterior limb of the gland, the upper surface of which has just been described as lying beneath the shell.
Thus the base of the gill passes in a slanting direction across the right-hand side of the kidney, the posterior end being dorsal to the apex of the gland, and the anterior end ventral to the right-hand corner.
K, Opening of the albuphrodite duct, which very soon becomes miniparous gland into P Y the hermaphrodite entwined in the spire of a gland - the duct.
Closed in a viscid secretion at the point where the albuminiparous gland opens into the duct intertwined with it; and on reaching the pcint where the spermathecal duct debouches they are impregnated by the spermatozoa which escape now from the spermatheca and meet the ova.
(From Owen.) of the liver or great digestive gland is found in the scorpions, where the axial portion of the digestive canal is short and straight, and the lateral ducts sufficiently wide to admit food into the ramifications of the gland there to be digested; whilst in the spiders the gland is reduced to a series of simple caeca.
From the ovo-testis, which lies near the apex of the visceral coil, a common hermaphrodite duct ve proceeds, which receives the duct of the compact white albuminiparous gland, Ed, and then becomes much enlarged, the additional width being due to the development of glandular folds, which are regarded as forming a uterus u.
This second duct has normally no spermathecal gland at its termination, which is simple and blunt.
Whether the closed primitive shell-sac of the slugs (and with it the transient embryonic shell-gland of all other Mollusca) is precisely the same thing as the closed sac in which the calcareous pen or shell of the Cephalopod Sepia and its allies is formed, is a further question which we shall consider when dealing with the Cephalopoda.
Similar observations were made by Laurie (17) in Lankester's laboratory (1890) with regard to the early condition of the coxal gland of Scorpio, and by Bertkau (41) as to that of the spider Atypus.
The name " coxal gland " needs to be carefully distinguished from " crural gland," with which it is apt to be confused.
A, prosomatic gastric gland (sometimes called salivary).
Poison-gland present whose duct traverses the nerve-collar.
Calciferous gland or dart-sac on the female duct.
- Embryo of Limnaeus stagnalis, at a stage when the Trochosphere is developing foot and shell-gland and becoming a Veliger, seen as a transparent object under slight pressure.
Ing gs, the bilobed arch sh, The primitive shell-sac or enteron or lateral vesicles shell-gland ° of invaginated endoderm, pi, The rectal peduncle or whichwill develop into liver.
To the right (in the figure) of the rectal peduncle is seen the deeply invaginated shell-gland ss, with a secretion sh protruding from it.
The shell-gland is destined in Limnaeus to become very rapidly stretched out, and to disappear.
The musky odour from which it derives its name is due to the secretion of a large gland situated in the inguinal region, and present in both sexes.
Kidneys, pancreas and the thyroid gland, also in muscle-plasma; " crystalline," a globulin occurring in two forms a and /3, is found in the lens of the eye; " egg-globulin " and " lactoglobulin " occur respectively in the white of egg and in milk.
In 1900 it was shown that the coxal gland of Limulus is provided with a very delicate thin-walled coiled duct which opens, even in the adult condition, by a minute pore on the coxa of the fifth leg (Patten and Hazen, 13A).
Previously to this, Lankester's pupil Gulland had shown (1885) that in the embryo the coxal gland is a comparatively simple tube, which opens to the exterior in this position and by its other extremity into a coelomic space.