262 THK HORSE. 



THE PRINCIPLES AND PRACTICE OF BREEDING FOR THE TURF AND 

 FOR GENERAL PURPOSES. 



THEORY OF GENERATION. 



Before proceeding to enlarge upon the practical manage- 

 ment of the breeding stud, it will be well to ascertain what are 

 the known laws of generation in the higher animals. 



The union of the sexes is, in all the higher animals, neces- 

 sary for reproduction ; the male and female each taking their 

 respective share. 



The office of the male is to secrete the semen in the testes^ 

 and emit it into the uterus of the female, where it comes in 

 contact with the ovu'm of the female — M'hicli remains sterile 

 without it. 



The female forms the ovuin in the ovary^ and at regular 

 times, varying in different animals, this descends into the uterus, 

 for the purpose of fructification, on receiving the stimulus and 

 addition of the sperm-cell of the semen. 



The semen consists of two portions — the spermatozoa, which 

 liave an automatic power of moving from place to place, by 

 which quality it is believed that the semen is carried to the 

 ovum ; and the sperra-cells, which are intended to co-operate 

 with the (jerm-cell of the ovum in forming the embryo. 



The ovum consists of the germ-ccll., intended to form part of 

 the embryo, — and of the yoll\ which nourishes both, until tlie 

 vessels of the mother take ujion themselves the task ; or, in ovip- 

 arous animals, till hatching takes jilace, and external food is 

 to be obtained. The ovum is carried down by the contractile 

 power of the fallopian tubes from the ovary to the uterus, 

 and hence it does not require automatic particles like the 

 semen. 



The embryo, or young animal, is the result of the contact 

 of the seinen with the ovum, iminediately after which the sperm- 

 cell of the former is absorbed into the germ-cell of the latter. 

 Upon this a tendency to inci-case or "grow " is established, and 

 supported at first, l»y the nutriment contained in the yolk of 

 tlie ovum, until the ombi-vo has attached iti^elf to the walls of 



