THE RABBIT. 319 



271. The coats of the .scrotal sac : these are, a layer of skin exter- 

 nally ; then a. layer of loose connective tissue, the dartos ; then a 

 layer of muscle, the cremaster, continuous with the internal oblique 

 muscle of the abdomen ; and, lastly, an internal lining of peritoneum, 

 the tunica vaginalis. 



/ 



272. The mesorchium, a double fold of peritoneum 

 suspending the testis and vas deferens to the dorsal wall 

 of the scrotal sac, after the manner of a mesentery ; its two 

 layers are continuous with the peritoneal lining of the sac 

 (tunica vaginalis), and are reflected over the testis. 



XXIX. Dissect away the kidneys, ureters, and scrotal 

 sacs from the surrounding parts : cut away the 

 symphysis pubis with bone forceps : cut through 

 the two corpora cavernosa (265) by which the 

 penis is attached to the ischia. Remove the 

 whole of the urinogenital organs from the body, 

 together with the posterior end of the rectum, 

 and pin them out in a dissecting dish, with the 

 dorsal surface uppermost, taking care to preserve 

 the natural relation of the parts. Carefully dis- 

 sect away all fat and connective tissue, gradually 

 separate the rectum from the other organs and 

 turn it aside, making out : 



273. The uterus masculinus (//.;#), a large sac, 

 slightly bilobed at its anterior end, and lying against the 

 dorsal side of the neck of the bladder. The vasa deferentia, 

 after curving round the ureters, are seen to pass between 

 this sac and the bladder. 



274. The prostate (//'), a glandular mass, in relation with 

 the neck of the bladder and the uterus masculinus. 



It consists of five lobes : an anterior (pr), so closely applied to the 

 dorsal wall of the uterus masculinus as to be almost inseparable from 

 it : another posterior (/>''), more prominent than the first, bilobed 

 anteriorly, and easily separable from the uterus masculinus; and two 



