xm 



PHYLUM CHORDATA 



461 



ftC" 



glands (p. gl.), open on the perineal space at the base of the penis : 

 two similar glands, the rectal glands (r. gl.), lie on either side of the 

 rectum. 



In the female the ovaries (Fig. 1109, ov.) are small ovoid bodies 

 attached to the dorsal wall of the abdomen behind the kidneys. 

 The Graafian follicles enclosing the ova form only very small rounded 

 projections on their outer surface. 



The oviducts in the anterior part of their extent (Fallopian 

 tubes, fl.t.) are very narrow and slightly convoluted. They open 

 into the abdominal cavity by wide funnel-shaped openings (fl.t'.) 

 with fimbriated or fringed margins. Posteriorly each passes into 

 a thick-walled uterus (r. ut.). The two uteri open separately into 

 a median tube, the vagina (va.). The vestibule (Fig. 1108, vb.), or 

 urinogenital canal, is a wide 

 median passage, into which 

 the vagina and the bladder 

 open. On its ventral wall 

 is a small, hard, rod-like 

 body, the clitoris (c. c.), 

 with a pointed apex (g. cL), 

 corresponding to the penis 

 of the male, and composed 

 of two very short corpora 

 cavernosa attached ant- 

 eriorly to the ischia, and 

 invested internally by a 

 soft, grooved corpus 

 spongiosum. The vulva, 

 or external opening of 

 the -vestibule, is bounded 

 laterally by two prominent 

 folds the labia majora. 



Development. - The 

 Rabbit is viviparous. The 

 ovum, which is of rela- 

 tively small size, after 

 it has escaped from its 

 Graafian follicle, passes 

 into the Fallopian tube, where it becomes fertilised, and then reaches 

 the uterus, in which it develops into the foetus, as the intra-uterine 

 embryo is termed. The young animal escapes from the uterus 

 in a condition in which all the parts have become fully formed, 

 except that the eyelids are closed and the hairy covering is 

 not yet completed. As many as eight or ten young are produced 

 at a birth, and the period of gestation, i.e., the time elapsing between 

 the fertilisation of the ovum and the birth of the young animal, is 

 thirty days. Fresh broods may be born once a month throughout 



FIG. 1110. Diagrammatic longitudinal section of a 

 Rabbit's embryo at an advanced stage of pregnancy. 

 a. amnion ; a. stalk of allantois ; al. allantois with 

 blood-vessels ; c. embryo ; ds. cavity of yolk-sac 

 (umbilical vesicle) ; ed. endodermal layer of yolk- 

 sac ; ed'. inner portion of endoderm ; ed". outer 

 portion of endoderm lining the compressed cavity 

 of the yolk-sac ; fd. vascular layer of yolk-sac ; 

 pi. placental villi ; r. space filled with fluid between 

 the amnion, the allautois and the yolk-sac ; sh. 

 subzonal membrane ; st. sinus terminalis. (From 

 Foster and Balfour, after Bischoff.) 



