. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. PISCES. Fig. 536. 1007. Viscera of the Herring (Clupea harengus). a, oesophagus ; b, c, stomach ; d, pyloric cceca ; e, intestine ; f, anus ; g, spleen ; h, h, ovary ; t, ovi- ducts ; k, air-bladder. ovarian capsule arises a short canal i, i, and these two ducts uniting form a common tube, through which the ova pass out of the body through an aperture,,/, situated immediately behind the anus. In the male the disposition of the genera- tive organs is precisely similar, the membrane contained in the two capsules secreting
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. PISCES. Fig. 536. 1007. Viscera of the Herring (Clupea harengus). a, oesophagus ; b, c, stomach ; d, pyloric cceca ; e, intestine ; f, anus ; g, spleen ; h, h, ovary ; t, ovi- ducts ; k, air-bladder. ovarian capsule arises a short canal i, i, and these two ducts uniting form a common tube, through which the ova pass out of the body through an aperture,,/, situated immediately behind the anus. In the male the disposition of the genera- tive organs is precisely similar, the membrane contained in the two capsules secreting mitt instead of spawn, which when expelled through the efferent duct and thus mixed with the water in the vicinity of the ova of the female, pre- viously deposited, impregnates them by asper- sion. Instances are recorded by Cavolini and others of a remarkable kind of hermaphrodism occasionally met with in Fishes presenting this type of structure, in which, while the generative capsule upon one side of the body contained a roe-secreting membrane, that of the other fur- nished milt, so that one half of the fish was male and the other female; such an arrange- ment, however, can only be looked upon as a lusus naturae, although regarded by some of the older naturalists as a normal occurrence. Among the Salmonidae a very interesting ar- rangement of the generative apparatus is met with, which would seem to offer an intermediate condition between that of the Lamprey and that of the ordinary osseous Fishes. In the Trout and Salmon for instance, the extensive folds of the ovarian membrane are only partially en- closed in an investing capsule, the interior of which communicates by means of a wide slit with the abdominal cavity. In the common Salmon (Salmo Salar, Linn.) the ovary is much reduced in its relative size when compared with that of the Lamprey or of the Eel, although the ova are still developed in the folds of an irregu- larly transversely plaited membrane. These folds and the
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