. Elementary text-book of zoology. Zoology. GASTROPODA—HETEROPODA. 49 large auditory vesicles each receive a long auditory nerve from the cerebral ganglion, and are characterised not only by the remarkable vibrations of the long tufted cilia of their epithelium, but also by the arrangement of the nerve cells (group of hair cells of the mai-n/d acustica round a large central cell, fig. 83). In addition numerous peculiar nerve-endings in the skin, which appear to serve the tactile sensation, and the so-called ciliated organ on the anterior side of the visceral sac, are present. The latter has th
. Elementary text-book of zoology. Zoology. GASTROPODA—HETEROPODA. 49 large auditory vesicles each receive a long auditory nerve from the cerebral ganglion, and are characterised not only by the remarkable vibrations of the long tufted cilia of their epithelium, but also by the arrangement of the nerve cells (group of hair cells of the mai-n/d acustica round a large central cell, fig. 83). In addition numerous peculiar nerve-endings in the skin, which appear to serve the tactile sensation, and the so-called ciliated organ on the anterior side of the visceral sac, are present. The latter has the form of a ciliated pit, under which is placed the gaiiglionic swelling of a nerve which Qc Te. Bm Fig. 521.—Male of Carinaria mediterranea (after Gegenbaur). P, foot; S, sucker ; O, mouth; Bm, buccal mass; M, stomach; Sp, salivary gland; L, liver; A, anus; CQ-, cerebral ganglion ; 2V, tentacles ; Oc, eye; Of, auditory vesicle ; BG, buccal ganglion; Pg, pedal ganglion; Mg, mantle ganglion; N, kidney; Si-, gills; At, auricle ; TV, ventricle ; As, anterior aorta ; Z, posterior branch of same ; T, testis ; Vd, vas deferens ; \\'p, ciliated furrow ; Pe, penis ; F, flagellum with gland. arises in the visceral ganglion; it has the value of an olfactory organ. The males are distinguished by the possession of a large copulatory organ, which projects freely on the right side of the body : the males of Pterotrachea also possess a sucker on the foot. In All'.intn an 1 Carinaria the sucker is present in both sexes. The te-tes and ovaries fill the posterior part of the visceral sac and are partially imbedded in the liver. The ducts, viz., vas deferens and oviduct, open on the right side of the body; the former at some distance from the organ of copulation, to which the sperm is conducted from the sexual opening in a ciliated furrow. The copulatory organ consi-ts VOL. II. 4. Please note that these images are extracted from scanned page images that may have been digitally enhanced for re
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectzoology, bookyear1884
