248 ANATOMY OF THE RABBIT 



When the study of these parts has been completed, the attach- 

 ments of the penis should be severed at the posterior border of the 

 ischium and the symphysis should be divided. Pressing apart the 

 two halves of the pelvis facilitates examination of the connections 

 of the deferent ducts with the common urinogenital tube and 

 related parts. Following this the urinogenital organs and pelvic 

 portion of the rectum may be dissected out and removed from the 

 body in a single piece without damage to anything except the 

 vessels supplying these organs, which must be severed with the 

 attaching connective tissue. The rectum should then be separated 

 from the urinogenital structures. 



The middle haemorrhoidal artery (a. haemorrhoidalis media), a branch 

 of the hypogastric, passes to the side of the rectum, to the urethra, and to the 

 seminal vescicle. The internal pudendal artery (a. pudenda interna), accom- 

 panied by the corresponding nerve and vein, passes to the side of the penis, giving 

 off the inferior haemorrhoidal artery to the terminal portion of the rectum 

 and to the associated rectal or anal gland. The latter is an elongated, paired 

 organ enveloping the rectum a short distance in front of the anus and pouring 

 into it an oily secretion. The rectum is connected with the root of the tail by 

 the rectocaudalis muscle, a somewhat spindle-shaped aggregation of smooth 

 muscle fibres, arising from the body of the second caudal vertebra, and inserted 

 a short distance forwards on the dorsal surface of the rectum. The sphincter 

 ani externus and sphincter ani internus are two closely related muscles 

 enclosing the rectum and urethra, the former arising from the dorsum of the tail. 



Immediately dorsolateral to the body of the penis and just under the skin lie 

 the paired inguinal glands. At each side, a nearly spherical white inguinal 

 gland and, closely associated, a brown inguinal gland pour their secretions 

 into the hairless inguinal spaces. The former gland is sebaceous, the latter a 

 modified sweat gland producing an odoriferous secretion. 



The following parts of the urinogenital system may be made out : 

 (a) The connection of the bladder with the outside of the body 

 through the urethra. It comprises a short prostatic portion 

 in relation to the genital ducts, a much longer membranous 

 portion traversing the pelvis, and a terminal cavernous 

 portion in the penis. 

 (6) The seminal vesicle (vesicula seminalis) lies on the dorsal 

 surface of the base of the bladder. It is a flattened median 

 glandular pouch, the forward-directed tip of which has. a 

 relatively thick muscular wall and is slightly divided, 

 corresponding with a bilobed character of the cavity within. 



