656 



ANATOMY OF VERTEBRATES. 



' descent ' of the testes are better marked, perhaps, in some Insec- 

 512 tivora than in Rodentia. In December the 



testes of the Mole lie on each side of the uri- 

 nary bladder, with the inverted cremasteric 

 pouch attached to the great end of the epididy- 

 mis : in March they are protruded into serous 

 sacs, which look like a continuation of the 

 abdominal cavity beneath the base of the tail. 

 The prostatic glands, which begin to increase 

 in February, acquire an enormous size and 

 conceal the urinary bladder towards the latter 

 end of March. The Cowperian glands lie 

 beneath the integument above the root of the 

 tail, and send their duct to terminate in the 

 urethral bulb. The penis, bent backward 

 upon itself, terminates in a very long conical 

 glans with an ossicle, lodged in a preputial 

 sheath, which projects freely, a short distance 

 below the anus. In a Cape-mole ( Chryso- 

 chloris) I found the testes near the kidneys ; 

 but the convolute course of the vasa deferen- 

 tia indicated their periodical movements. The 

 accessory glands are better differentiated into 

 6 vesicular ' and e prostatic ' than in Talpa. 



In the Hedge-hog the vesicular glands, 

 which become enormous at the rut, lie 

 mainly behind the urinary bladder ; the 

 flattened mass of prostatic glands rises in 

 front : they are supported by folds of perito- 

 neum. The Cowperian glands, as in the 

 Mole, are extra-pelvic, behind the ischia, and accordingly reach 

 513 the urethral bulb by very long ducts. r The penis 



is long and bent when at rest. There are two 

 6 levatores ' which rise from the ischial tuberosi- 

 ties behind the i erectores : ' passing along* the 

 sides of the penis, their tendons meet upon the 

 6 dorsum ' near the reflection of the long prepuce, 

 crossing the ( vena dorsalis ' and inserted into the 

 6 ossiculum glandis ' : the urethra opens upon a 

 special process which projects beyond the main 

 body of the glans. In the Shrews, temporary 

 receptacles in the perinaeum receive the enlarged testes during 

 the rut; but do not project, as a scrotum. The epididymis 



Spermatozoa, a, of the Rat : b 

 of the Mouse : raagn. cccvi. 



Spermatozoa, Squirrel 



Iliagll. CCCVI. 



