HADRUMETUM, a town of ancient Africa on the southern extremity of the sinus Neapolitanus (mod.
By coalescence of the endoderm-layers, the coelenteron may be reduced to vessels, usually eight in number, opening into a ring-sinus surrounding the pore.
There are no lacunar blood spaces with ill-defined or absent walls except for a sinus surrounding the intestine, which is at least frequently present.
Small arm-sinus, containing musclefibres.
The dorsal branch sends a blind twig into each of the diverticula of the dorsal mantle-sinus, the ventral branch supplies the nephridia and neighbouring parts before reaching the ventral lobe of the mantle.
A considerable length of the toga was allowed to hang from the left shoulder; the remainder was passed round the body so as to rise like a baldric (balteus) from the right hip to the left shoulder, being folded over in front (the fold was called sinus), then brought round the back of the neck so that the end fell over the right shoulder; the hanging portion on the left side was drawn up through the sinus, and bulged out in an umbo (Plate, fig.
In these the furcal branches are linear or rudimentary, the shell is without rostral sinus, and, besides distinguishing characters of the second 2ntennae, they have always a branchial plate well developed on the first maxillae, which is inconstant in the other tribe.
The blood makes its way by large veins to a venous sinus which lies in the middle line below the heart, having the paired renal organs (nephridia) placed between it and that organ.
At their opposite ends the dorsal and ventral vessels are probably connected with one another by means of a splanchnic sinus surrounding the stomach.
Sc, Sinus canal in supra-occipital.
The whole sinus venosus has become part of the right atrium.
The dorsal vessel also communicates with the ventral vessel indirectly by the intestinal sinus, which gives off branches to both the longitudinal trunks, and by tegementary vessels and capillaries which supply the skin and the nephridia.
The difference is that it is broken up into a complex sinus system.
Here also the blood system has no communication with the sinus system of the coelom.
Dorsalwards into the peri - cardial sinus through fine perforations of its floor, and so makes its way into the heart again.
Of the families Belo- stomatidae, Nepidae, Corixidae and Hydrometridae have a pulsating sac at each knee-joint to assist the flow of blood through the legs, while in dragon-flies and locusts (Acridazdae) there is a ventral pulsating dia phragm, which forms the roof of a sinus enclosing the nerve-cords.
(3) The muzzle more or less shortened, the frontal sinus enlarged, and the cranium elevated and diminished in capacity.
These spaces are as follows: - (i.) the great arm-sinus; (ii.) the small arm-sinus together with the central sinus and the peri-oesophageal sinus, and in Discinisca and Lingula, and, to a less extent, in Crania, the lip-sinus; (iii.) certain portions of the general body cavity which in Crania are separated off and contain muscles, &c.; (iv.) the cavity of the stalk when such exists.
The great arm-sinus of each side of the lophophore lies beneath the fold or lip which together with the tentacles forms the ciliated groove in which the mouth opens.
These sinuses are completely shut off from all other cavities, they do not open into the main coelomic space nor into the small arm-sinus, nor does the right sinus communicate with the left.
The small arm-sinus runs along the arms of the lophophore at the base of the tentacles, and gives off a blind diverticulum into each of these.
In the region of the mouth where the two halves of the small arm-sinus approach one another they open into a central sinus lying beneath the oesophagus and partly walled in by the two halves of the ventral mesentery.
This sinus is continued round the oesophagus as the peri-oesophageal sinus, and thus the whole complex of the small arm-sinus has the relations of the so-called vascular system of a Sipunculid.
In Discinisca and Lingula there is further a lip-sinus or hollow system of channels which traverses the supporting tissue of the edge of the mantle and contains muscle-fibres.
In Crania, where only indications of the lip-sinus occur, there are two other closed spaces.
The posterior occlusor muscles lie in a special closed space which Blochmann also regards as coelomic. The posterior end of the intestine is similarly surrounded by a closed coelomic space known as the peri-anal sinus in which the rectum lies freely, unsupported by mesenteries.
Interior of dorsal small arm-sinus and, running valve.
The chief arm-nerve traverses the lophophore, being situated between the great arm-sinus and the base of the lip (figs.
The under arm-nerve, which lies between the small arm-sinus and the surface, supplies nerves to the muscles of both arm-sinuses (figs.
Their minute structure is closely similar in the two cases; the leaf-like plates receive blood from the great sternal sinus, and serve as respiratory organs.
[How the inversion of the nerve-end-cells and their connexion with the nerve-fibres is to be reconciled with the condition found in the adult, or with that of the monostichous eye, has not hitherto been explained.] (From Korschelt and Heider.) The great pericardial sinus is strongly developed in both animals.
The venous blood is conducted from the tissues to a large sinus on either side above the pallial groove, and from this sinus passes to the gills by an afferent vessel in each gill on the internal or pedal margin of the axis.
The aorta is not independent as in Chitons, but is a sinus like the other channels of the circulation.
Tekir), an ancient city of Caria in Asia Minor, situated at the extremity of the long peninsula that forms the southern side of the Sinus Ceramicus or Gulf of Cos.
The afferent vessel of the' ctenidium receives blood from the vena cava or principal blood-sinus of the body, the efferent vessel opens into the auricle of its own side.
When it is slit open from in front a longitudinal ridge is seen in its posterior wall, which is called the verumontanum or crista urethra, and on each side of this is a longitudinal depression, the prostatic sinus, into which numerous ducts of the prostate open, though some of them open on to the antero-lateral surface.
Pecten; shell orbicular, with equal auriculae; without a byssal sinus; British.
Chlamys; anterior auricula the larger and with a byssal sinus; British.
With a sinus; freshwater.
Veneridae.-Foot well developed; pallial sinus shallow or absent.
Glaucomyidae.-Siphons very long and united; foot small; shell thin, with deep pallial sinus; fresh or brackish water.
Geniculated; pallial line without sinus; two adductors, Cardium; British.