Chap. III.] GENERAL ANATOMY. 43 



body (adrenal). From the inner edge (hilus) of each kidney a 

 .ureter passes back and enters the bladder (16, U. B.\ which is an 

 oval sac lying at the posterior end of the coelom. It communi- 

 cates with the exterior in a manner which differs considerably 

 in male and female. 



There is no connection between the testis of the male and the 

 kidney. The testes (Ts.) of the rabbit undergo, during develop- 

 ment, a remarkable change of position, by which they pass 

 out of the coelom, and come to lie in little pouches of the 

 skin below the pelvic arch, one on either side of the penis. 

 They are provided with special ducts (vasa, deferentia), which 

 will be seen to form a loop on either side over the ureters. They 

 then join the urethra, which forms the canal of the penis. 



The ovaries in. the female are somewhat elongated oval bodies, 

 upon which, in the adult, are a number of minute projections, 

 the Graqfian follicles, which contain the ova. Close to each ovary 

 is the funnel-shaped opening of the Fallopian tube, into which 

 the ova are received when they are shed. This is somewhat 

 convoluted, but gradually expands to form the uterus, in which 

 the ova, fecundated by spermatozoa within the Fallopian tube, 

 undergo prenatal development. The two uteri unite in the 

 middle line into the common vagina, which opens into the vesti- 

 bule leading to the external aperture or vulva. 



5. The Nervous System. At the back of the peritoneal cavity 

 may be seen nerves ; several of these in the region of the arm 

 form a brachial plexus, those in the thorax run out between the 

 ribs, and several of those in the region of the hind-limb form a 

 lumbo-sacral plexus. The sympathetic nerve chain may be seen in 

 the thoracic region, lying on the heads of the ribs on either side of 

 the vertebral column ; while in the region of the neck a flat nerve, 

 lying beneath the carotid artery, alongside a rounded cranial 

 nerve, is a continuation of the sympathetic chain. 



The brain must be displayed by breaking away the roof of the 

 skull, and the spinal cord by removing the arches of the more 

 anterior vertebrae. The brain is relatively very much larger, and 

 considerably more complex in form than that of the frog, and it fits 

 much more closely into its bony case. A tough membrane (dura 



