THE SEMEN. 



455 



an inch in lengtli. The body often contains a minute spot, and at its junction 

 with the naiTow filament or tail, there is frequently a slight thickening, or 



Fig. 324. — Spermatic Cells and 

 Filaments of the Bull undergo- 

 ing DEVELOPMENT (from K(511iker). 

 ~i ' 



1, spermatic cells with one or two 

 nuclei, cue of them clear ; 2, 3, free 

 nuclei with spermatic filaments form- 

 ing ; 4, the filaments elongated and 

 the 1x)dy widened ; 5, filaments nearly 

 fully developed. 



projecting fringe or collar, which 

 is most apparent in corpuscles not 

 fully developed. 



The sijermatic corjiuscies are pro- 

 duced by a process of transforma- 

 tion taking place within the cells 

 which occiipy the seminiferous 

 tubes of the body of the testicle : 

 it is completed in the progress of 

 the cells through the rete testis and 



vasa efferentia, in which last most of the spermatic filaments are free, and have 

 acquired their vibratory motile jjower. The process of transfonnation was first 

 clearly sho-mi by KoUiker in mammalia, in which he described the spermatic 

 cells as having formed within them by division a smaller or greater niunber of 



Tig. 325. 



Fig. 825. — Escape op the Sjermatic Cor- 

 puscles FROM THEIR CeLLS, IN THE SAME 



Animal. 



1, spermatic cell containing the spermatozoon 

 coiled up within it ; 2, the cells elongated by the 

 partial uncoiling of the spermatic filament ; 3, 

 a cell from which the filament has in part become 

 free ; 4, the same with the body also pai-tially 

 fi'ee ; 5, spermatozoon from the epididymis with 

 vestiges of the cell adherent ; 6, spermatozoon 

 from the vas deferens showing the small enlarge- 

 ment, b, ou the filament. 



nuclei, each one of which gives rise to a 



filamentous corpuscle. (Handbuch der Ge- 



webelehre, 1867, p. .527, and Zeitsch. f. Wissen, 



Zool., vol. vii.) Subsec|uent observers have in 



the mam confirmed the views of Kolliker, the 



only difference of imporiance between them 



being that some, as Merkel and La Valette St. 



George, appear to regard the internal progeny 



of the spermatic cells as complete cells rather 



than nuclei. Adopting the language of the 



latter observers, it appears that the so-called 



body or head of the corpuscle is produced by a 



change of f onn and consistence in the part of 



the cell containing the nucleus, which projects more and mxjin to one side : the tail 



or filament begins as a fine-pouited projection from the opposite side of the 



cell, and extends rapidly as a filament, at first within the cell-wall, bulging 



out the wall as it increases in length, and finally breaking through its confine- 



