310 ON GENERATION. 



It is certain that the cock in coition emits his ' geniture/ 

 commonly called semen, from his sexual parts, although he has 

 no penis, as I maintain ; because his testes and long and ample 

 vasa deferentia are full of this fluid. But whether it issues in 

 jets, with a kind of spirituous briskness and repeatedly as in 

 the hotter viviparous animals, or not, I have not been able to 

 ascertain. But as I do not find any vesiculse containing semen, 

 from which, made brisk and raised into a froth by the spirits, it 

 might be emitted ; nor any penis through whose narrower orifice 

 it might be forcibly ejaculated, and so strike upon the interior 

 of the hen ; and particularly when I see the act of intercourse 

 so rapidly performed between them; I am disposed to believe 

 that the parts of the hen are merely moistened with a very 

 small quantity of seminal fluid, only as much as will adhere to 

 the orifice of the pudenda, and that the prolific fluid is not 

 emitted by any sudden ejaculation ; so that whilst among animals 

 repeated ejaculations take place during the same connection, 

 among birds, which are not delayed with any complexity of 

 venereal apparatus, the same object is effected by repeated con- 

 nections. Animals that are long in connection, copulate rarely ; 

 and this is the case with the swan and ostrich among birds. 

 The cock, therefore, as he cannot stay long in his connections, 

 supplies by dint of repeated treadings the reiterated ejaculations 

 of the single intercourse in other animals ; and as he has neither 

 penis nor glans, still the extremities of the vasa deferentia, 

 inflated with spirits when he treads, become turgid in the 

 manner of a glans penis, and the orifice of the uterus of the 

 hen, compressed by them, her cloaca being exposed for the oc- 

 casion, is anointed with genital fluid, which consequently does 

 not require a penis for its intromission. 



We have said, however, that such was the virtue of the semen 

 of the cock, that not only did it render the uterus, the egg in. 

 utero, and the vitelline germ in the ovary, but the whole hen 

 prolific, so that even the germs of vitelli, yet to be produced, 

 were impregnated. 



Fabricius has well observed, that the quantity of spermatic 

 fluid contained in the testes and vasa deferentia of the cock 

 was large ; not that the hen requires much to fecundate each 

 of her eggs, but that the cock may have a supply for the large 

 number of hens he serves and for his repeated addresses to them. 



