CHAPTER IV. 



EMBRYOLOGY, IMPREGNATION, 

 CONCEPTION. 



Transmission of life has always been one of 

 the greatest mysteries with which investigators 

 have had to deal. As the higher mammalian 

 animals are all the result of evolution spread- 

 ing over millions of years, so the development 

 of the life-transmitting agents must have been 

 brought about through evolution from mere cel- 

 lular fission of protoplasmic bodies up to the 

 present complicated process. It was not until 

 1677, as is commonly accepted, that the seminal 

 animalcules were discovered and it was not 

 until well into the nineteenth century that much 

 was known of their history and growth. Actual 

 physiological transmission of life, transmission 

 of physical and mental inheritance and the de- 

 velopment of the fetus in the womb, with all 

 the concomitant maze of mystery existing in 

 reversion, accidental sports and the transmis- 

 sion of acquired characteristics, form one of the 

 most intricate problems with which science has 

 to deal. It is impossible to go into any ex- 

 tended discussion of this subject here. There- 

 for the merest outline must suffice. 

 In the mare the two ovaries are situated in 



35 



