HISTORY OF THE FERTILIZATION PROBLEM 5 



against a certain Dr. Dalen Patius, who claimed to have 

 seen the human form, "the two naked thighs, the legs, 

 the breast, both arms, etc., the skin being pulled up 

 somewhat higher did cover the head like a cap. " 



Leeuwenhoek states that he can find nothing of the 

 sort, but he adds: 



I put this down as a certain truth, that the shape of the 

 human body is included in an animal of the masculine seed; 

 but that a man's reason shall dive or penetrate into this mystery 

 so far, that in anatomizing one of these animals of the masculine 

 seed we should be able to discover the entire shape of the human 

 body, I can not comprehend. 



In a letter dated two weeks later he distinguishes 

 two sorts of these animalcules, and concludes that the 

 one -sort is male and the other female. 



In France, in the year 1694, Nicholas Hartsoeker 

 claimed to have been the first to have discovered the 

 spermatozoa, more than twenty years previously, 

 although he did not publish until 1678, a year later 

 than Leeuwenhoek's publication. Hartsoeker's ideas 

 are characterized by a high degree of precision. He 

 believes that each spermatozoon conceals beneath its 

 " tender and delicate skin" a complete male or female 

 animal. The egg is merely a source of nourishment 

 for the real germ contained in the spermatozoon. 

 In birds the spermatozoon enters an egg to be nourished; 

 there is but a single opening in the egg, situated over the 

 so-called germ, and this opening closes after a single 

 spermatozoon is admitted; but if two spermatozoa enter 

 they unite and form a double monster. In mammals 

 the tail of the spermatozoon is the umbilical cord; this 

 unites with the ovum, i.e., the placenta, and the latter 



