nir. - HI 



>N Eft, 



383 



follicle-like *t met lire* b. come hollow ami t bu* convert, d into v <//,/',/.// 

 (tut/ml/"-, who*e epithelial cells gradually grow out into long cylin 

 The greater part of the->e become -eminal mot her cells, which by 

 many repeated division* are converted into sixty seminal cells, each 

 of which is metamorpho-ed into a -emiiial filament. Since the 

 filament s derived from each 

 seminal mother-cell alua\> 

 arrange themselves parallel 

 to one another, it is easily 

 understood whv he fore the =c 

 e.ttainment of complete 

 maturity the seminal tila- 

 ments are found united in 

 great numbers into bund lev. 



\Vttereas the testis, like 

 the cm/-//, itnnvs its specific 

 histological components Di- 

 rectly from the genninnJ 

 epithelium, it acquires its 

 efferent ducts from '/>' 

 irriinitive kidney. As in 

 the female, so also in the j 

 male, epithelial shoots, the 

 sexual cords (genital canal* 

 of HOFFMANN), grow from 

 the primitive kidney to- 

 ward the testis ; in the 

 Amphibia they arise as 

 proliferations from the 

 cells of the wall of certain 

 Malpighian corpuscles ; in 

 the Selachians, on the con- 

 trary, they sprout out in a 

 *omewhat different manner 

 from the ciliate funnel*. 



Arrived at the base of the t *ticular ridge, they are joined together 

 into a longitudinal canal, from which tine tubules are sent still 

 farther into the substance of the testis, where they unite with the 

 structures that take their origin in the germinal epit helium. As 

 figure -IS Ji shows, the efferent tubules (sc) in Selachians at 

 first apply their blind ends to the ampulla?, and enter into open 



