i8 INTRODUCTION TO SEXUAL PHYSIOLOGY 



receptacles and are afterwards withdrawn, there being no true 

 scrotum. In some rodents (e.g. the hare and rabbit) the testes 

 descend at rut into a true scrotum, and subsequently pass back 



m^.. 



/ 













0^^ 





-* ® 











xj/- 



Fig. 9.-Section through portion of two seminiferous tubules 



in testis of rat. 



«, Basement membrane ; h, spermatogonium ; r, spermatocyte ; o? sper- 



'matozoa in cavity of tubile ; ., interstitial tissue containing vessels. 



through the inguinal canals. In other animals, such as the ram, 

 there is only a slight withdrawal after rut. In man it occasionally 

 happens that the testes retain their original position, which is 

 approximately the same as that of the ovaries in the body cavity 

 of the female, or more frequently they traverse only part of the 



