25 



ELEMENTS OF HISTOLOGY. [Ch ap .xxxi. 



middle piece, and terminating as the tail, has been ob- 

 served (H. Gibbes). 



328. The seminal tubules of each compartment 

 or lobule empty themselves into a short, more or less 

 straight, tubule the vas rectum. -- This is narrower 



Fig. 139. Various kinds of Spermatozoa. 



A, Spermatozoon of guinea-pig not yet completely ripe ; B, the same seen side- 

 "ways, the head of the spermatozoon is flattened from side to side ; c, a 

 spermatozoon of the horse ; D, a spermatozoon of the newt. 



than the seminal tubule, and is lined with a single 

 layer of polyhedral or short columnar epithelial cells. 

 The vasa recta form, in the corpus Highmori, a dense 

 network of tubular channels, which are irregular in 

 diameter, being at one place narrow clefts, at another 

 wide tubes, but never so wide as the seminal tubules ; 

 this network of channels is the rete testis. 



329. (2) The epididymis. From the rete testis 

 we pass into the vasa ejferentia, each being a tube 



