CHAPTER IV. 



THE SEMINAL FLUID, AND THE MALE ORGANS OF 



GENERATION. 



THE mature egg is not by itself capable of being developed into the 

 embryo. If simply discharged from the ovary and carried through the 

 oviducts to the exterior, it soon dies and is decomposed, like any other 

 portion of the body separated from its connections. It is only when 

 fecundated by the seminal fluid of the male, that it is stimulated to con- 

 tinued development, and becomes capable of more complete organiza- 

 tion. 



The product of the male generative organs is a colorless, somewhat 

 viscid, albuminous fluid, containing minute filamentous bodies, the sper- 

 matozoa. This name has been given to the bodies in question on ac- 

 count of their exhibiting, when recently discharged, a very active and 

 continuous movement suggesting the idea of an independent animal 

 organization. 



Anatomical Characters of the Spermatozoa. The spermatozoa of man 

 (Fig. 230, a) are about .045 millimetre in length, according to the mea- 

 surements of Kolliker. Their anterior extremity presents a somewhat 

 flattened triangular-shaped enlargement, termed the "head," which con- 

 stitutes about one-tenth part the entire length of the spermatozoon. 

 The remaining portion is a slender filamentous prolongation, called the 

 "tail," which tapers gradually backward, becoming so exceedingly deli- 

 cate toward its extremity, that it is difficult to be seen except when in 

 motion. There is no further organization visible in any part of the 

 spermatozoon ; and the whole appears to consist, so far as can be seen 

 by the microscope, of a homogeneous substance. The terms head and 

 tail, as remarked by Bergmann and Leuckart, 1 are not used, when de- 

 scribing the different parts of the spermatozoon, in the same sense as 

 that in which they would be applied to the corresponding parts of an 

 animal ; but simply for the sake of convenience, as one might speak of 

 the head of an arrow or the tail of a comet. 



In the lower vertebrate animals, the spermatozoa have the same gen- 

 eral form as in man ; that is, they are filamentous bodies, with the ante- 

 rior extremity more or less enlarged. In the rabbit, the head is roundish 

 and flattened in shape, somewhat resembling a blood globule. In the 

 rat (Fig. 230, 6) they are much larger than in man, measuring nearly 

 0.20 millimetre in length. The head is of a conical form, about one- 



1 Vergleichende Physiologie. Stuggart, 1852. 



(695) 



