130 



Anatomy of the Rabbit. 



nosus muscle, the origin of which occupies a similar position on the 

 ischium. The penis is also attached to the symphysis hy a short but 

 stout suspensory ligament (lig. suspensorium) and by a small pubo- 

 cavernosus muscle lying between the latter and the ischiocavernosus. 



The attachments of the penis should be severed and the symphysis 

 divided. By pressing apart the two sides. of the pelvis the urinogenital 

 tubes, with the penis and the pelvic portion of the rectum, may be 

 dissected out and removed from the body. 



The middle haemorrhoidal artery 



(a. haemorrhoidalis media), a 

 branch of the hypogastric, passes 

 to the side of the rectum and to 

 the seminal vesicle. The internal u.u. — 

 pudendal artery (a. pudenda inter- 

 na), accompanied by the corres- 

 ponding 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 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 ver- 

 tebra, 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 i 



arising from the dorsum of the tail. 



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 com- 

 prises a short pros- 

 tatic portion in rela- 

 tion to the genital 

 ducts, a much 

 longer membranous 

 portion traversing 

 the pelvis, and a terminal cavernous portion in the penis. 



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

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

 pouch, the anterior, slightly divided tip of which is directed 

 forward. 



Fig. 45. The male urinogenital ducts and related 

 structures, viewed from the lateral surface. After 

 Rauther: a., anal aperture; bu., bulbourethral 

 gland; c.c, corpus cavernosum; d.d., ductus de- 

 ferens; g.a., anal (rectal) gland; g,i., inguinal gland; 

 g.p., glans penis; par., paraprostatic glands; pr., 

 prostate; r., rectum; ur., ureter; u.v., urethra 

 (membranous portion); v.s., seminal vesicle; v.u., 

 urinary bladder. 



