. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. Embryo of Emys amazonica. Tlie shell has been removed and the membranes of the egg laid open and spread out. a, the anmion, turned back so as to display the their natural position; b, the allantois, with its enclosed ramifications of blood-vesse's; c, the yolk, which is in communication with the intestinal canal by means of the vitelline duct, which enters the abdomen through the opening of the navel. state of maturity, the disposition of the allantois and of the vitelline sac is found to be precisely similar to that of
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. Embryo of Emys amazonica. Tlie shell has been removed and the membranes of the egg laid open and spread out. a, the anmion, turned back so as to display the their natural position; b, the allantois, with its enclosed ramifications of blood-vesse's; c, the yolk, which is in communication with the intestinal canal by means of the vitelline duct, which enters the abdomen through the opening of the navel. state of maturity, the disposition of the allantois and of the vitelline sac is found to be precisely similar to that of these structures in the egg of a bird, as will be at once evident on reference to the annexed figure, representing the anatomy of the ovum of the Monitor at a very advanced state of maturation. The allantoic sac, which serves for the respiration of the embryo during the earlier stages of its growth, is richly vascular, and communicates as usual with the anterior part of the cloacal cavity, the so-called urinary bladder being, in fact, merely a remnant of this apparatus. The vitelline sac communicates freely with the abdominal cavity at the umbilicus, its contents being conveyed into the commence- ment of the intestinal canal through a ductus vitello-intestinalis (Jig. 244, e): at a still later Fig. Anatomy of a very young Fetus of the 1'iper ( Vipera Berus). \After Otto.) a, the yolk-bag, b, the amnion ; c, the umbilical cord; d, ductus vitello-intestinalis; e, opening of the ductus vitello-intestinalis between the longi- tudinal folds of the mucous membrane of the small intestines;/', intestine partially laid open and cut across; g, h, continuation of the intestine as far as the anus; i, i, rudiments of the ovaria; k, k, the kidnevs; /, anus. Y 2. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Todd,
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Keywords: ., bo, booksubjectanatomy, booksubjectphysiology, booksubjectzoology
