Archive image from page 68 of The cyclopædia of anatomy and. The cyclopædia of anatomy and physiology cyclopdiaofana05todd Year: 1859 Common adder, in which the ova have descended to occupy both oviducts, five in the right, and three in the left: the infundibulum is shown in each ovi- duct; a'a, the right and left ovaries, each forming a sac, opening anteriorly near the infundibulum for the discharge of the ova, which, when ripe, fall into the interior of the sac, and thence pass into the oviduct. pear to be so direct, and there are various other means by which the ova, when they have escaped
Archive image from page 68 of The cyclopædia of anatomy and. The cyclopædia of anatomy and physiology cyclopdiaofana05todd Year: 1859 Common adder, in which the ova have descended to occupy both oviducts, five in the right, and three in the left: the infundibulum is shown in each ovi- duct; a'a, the right and left ovaries, each forming a sac, opening anteriorly near the infundibulum for the discharge of the ova, which, when ripe, fall into the interior of the sac, and thence pass into the oviduct. pear to be so direct, and there are various other means by which the ova, when they have escaped into the abdominal cavity, reach the open extremity of the oviduct. It is in the class of fishes that the transi- tion occurs from the higher to the lower type of organisation of the ovaries and oviducts. In all of them the ovules are formed in ova- rian follicles, and escape by dehiscence from these follicles; but there are several modifi- cations of the relation between the oviduct and ovary among them. 1st. In the sharks and rays, as already stated, the arrangement is nearly similar to that existing in higher ani- mals. The ova, which are of large size, come to maturity singly, or in small numbers at once: on being discharged externally from the ovarian capsules, they pass into the oviduct, and there receive a considerable addition from this organ. The majority of them, as previously stated, are oviparous, and in them a hard covering is formed by a peculiar glandular organ connected with the oviduct; in a few which are ovoviviparous, as the common dog- fish, torpedo, &c., the external covering of the ovum is membranous and soft. 2nd. In the sturgeon and in the lamprey the oviduct is very short ; still, as it opens superiorly into the abdominal cavity, the relation may be considered the same as in the previous ex- amples. 3rd. In the genus salmo and in Fig. 39. B Ovaries and oviduct of an osseous Fish. A. Sketch of the two largely developed saccu- lated ovaries of an os
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Keywords: 1850, 1859, anatomy, archive, book, bookauthor, bookdecade, bookpublisher, booksponsor, booksubject, bookyear, drawing, historical, history, illustration, image, london_sherwood_gilbert_and_piper, mblwhoi_library, page, physiology, picture, print, reference, todd_robert_bentley_1809_1860, vintage, zimmermann_a_albrecht_b_1860, zoology
