124 GLANDS. 



phous. The movements of the spermatozoa con- 

 tinue a long time after death (10 to 24 hours) ; 

 water and acids arrest them, but they are renewed 

 again by the application of slightly alkaline liquids. 

 of These elements, which constitute the essential por- 

 tion of the seminal secretion, are developed in the 

 following manner : On examining the epithelium of 

 the tubuli seminiferi it is observed that its central 

 cells are generally more voluminous than the rest, 

 and give evidence of a more or less active process of 

 endogenous vegetation (PL XXL fig. V.) ; thus, some 

 cells are to be seen enclosing as many as ten nuclei. 

 In addition to the nucleolus, which is visible in each 

 nucleus, in the shape of a brilliant spherical vesicle, 

 there is also observable upon one point of. its peri- 

 phery an elongated spot (fig. V. 3), from which shortly 

 a long and delicate filament takes its origin, which 

 coils, upon itself as it increases in size, occupying 

 always the periphery of the nucleus (fig. V. 7). As 

 soon as the nuclei have attained their full develop- 

 ment, the parent cell, being no longer able to contain 

 them, bursts, and they thus become free. Its ele- 

 ments subsequently become disintegrated and disap- 

 pear. The tail of the spermatozoon then uncoils itself 

 (fig. V. 8), afterwards its head becomes disentangled, 

 and its development is accomplished. 



In the testes of the guinea-pig, we have, on several 

 occasions, traced the successive transformations which 

 the epithelial cell undergoes in giving origin to sperma- 

 tozoa, and have always witnessed the occurrence of the 

 phenomena taking place as above described ; that is, 

 each nucleus distinctly gives origin to a spermatozoon. 



