OF REPRODUCTION. 93 



230. Galen set forth an opinion diametrically opposite to that of 

 the celebrated naturalist of Stagyra; he insists that the embryo is 

 produced from the semen of the male, and that the material furnished 

 by the woman serves solely for its nourishment. 



231. R. De Graaf thought he could demonstrate that all animals 

 come from an egg, and says that in the human species itself, the 

 germs exist in the ovary, in the form of ovules, or little transparent 

 vesicles. The ancient doctrine, entitled the system of mixed germs, 

 was soon generally abandoned, while the new hypothesis, known as 

 the system of ovules, spread with the rapidity of lightning. This is 

 the doctrine that prevails at the present day; but as may well be 

 supposed, it has not reached the nineteenth century without hav- 

 ing experienced numerous modifications. According to De Graaf, 

 Meckel, &c., the little ovule is only a kind of rudimental embryo, 

 which is only waiting for life in order then to commence its own de- 

 velopment; and this life can only be imparted to it by the prolific 

 semen of the male; according to Ruysch and Haller, the seminal 

 liquor is conveyed unaltered, by the Fallopian tube, to the ovary, 

 while others think that a very subtle vapor, an aura seminalis, only 

 is detached from it, and which produces the same effect; several wri- 

 ters have advanced the opinion, that the semen, at first absorbed in 

 the vagina or uterus, and carried from thence into the torrent of the 

 circulation, does not return to the ovary to fecundate a vesicle until 

 it has undergone several elaborations. 



232. Soon after the discovery of the ovules. Ham, Harstoecker, 

 and Lewenhoeck affirmed that the germs exist, quite formed, in the 

 reproductive fluid of the male; that these germs, which they called 

 animalcules, are living; that a single drop of sperm contains many 

 thousands of them; that being projected in the act of coition into 

 the uterine cavity, they all perish with the exception of one, or more, 

 which are fortunate enough to reach the Fallopian tube; that one 

 of them reaches the ovary, enters and lodges in % vesicle prepared 

 for that purpose, and afterwards returns to the womb in the shape 

 of a litde ovum, &;c. Hence is established a new system, since 

 called the system of animalcules, a system which gives to man an 

 immense share in the act of fecundation, while the ovular hypothesis, 

 as understood by De Graaf, attributes almost the whole of it to the 

 woman. 



233. Harvey, supported by the munificence of a great king; Hal- 

 ler, with his extraordinary talents; Spallanzani, with that good faith 

 and spirit of observation for which he was so remarkable; for the 

 purpose of clearing up this great question, multiplied their experi- 

 ments almost infinitely, and their labors have led, or seem to lead, 



9* 



