the male sperm, consider the woman only necessary to 

 receive and contain it until the appropriate stage 

 of development is reached. But the evident likeness 

 of one child with the father and another with the 

 mother contradicts these theories which impute the 

 essential force of conception either to the father or 

 to the mother alone. Epigenesis, according to which 

 the embryo originates from the mixing of male sperm 

 with female, is also incorrect; for it was proved 

 long ago, by de Graaf , that women do not have true 

 sperm. 27 



Noting that in animals having external fertilization, 

 particularly fish, the milt cannot mix with the roe because 

 the roe are covered with a jelly-like membrane, Vellanskii 

 concluded that fertilization of the sperm is not represented 

 mechanically or chemically, but dynamically, and he applied 

 this conclusion to the higher vertebrates, in which "conception 

 takes place by the effect of the male sperm on the follicles 

 which are present in their maternal ovaries, where the 

 sperm are present giving life, and the follicles are given 

 life, the first being equivalent to the polyp, and the second 

 corresponding to the fungus. "2° 



Vellanskii could not, of course, avoid the well known 

 fact that in the seminal fluid there are numerous active bodies 

 with tails. He called the spermatozoids cercariae, assigning 

 to them "the fertilizing property of the semen." 



Cercariae . . . reach the ovary in the manner of polyps; 

 they find there the Graafian follicles like the fungus 

 corresponding to them; and these together produce a 

 single creature, the embryo of the animal .... 

 The follicles given life by the polyp swell and blow 

 up, and the polyp within the flowing fluid forms the 

 embryo, which does not originate from the mixing of 

 sperm with the fluid of the follicle, but is a 

 transformation of many cercariae into one organism. 29 



27. Ibid ., pp. 413 - 414. 



28. Ibid ., p. 417. 



29. Ibid., p. 421. 



157 



