172 ON GENERATION. 



uterus the foetus is engendered. And it was on this account 

 that Fabricius admitted two seats of generation : one internal, 

 the uterus ; another external, the ovum. But he would have 

 had more reason, in my opinion, had he called the nest, or place 

 where the eggs are laid, the external seat, that, to wit, in which 

 the extruded seed or egg is cherished, matured, and perfected 

 into a foetus ; for it is from the differences of this seat that the 

 generation of oviparous animals is principally distinguished. 

 And it is, indeed, a thing most worthy of admiration to see 

 these creatures selecting and preparing their nests with so much 

 foresight, and fashioning, and furnishing, and concealing them 

 with such inimitable art and ingenuity ; so that it seems impe- 

 rative on us to admit in them a certain spark of the divine 

 flame (as the poet said of bees) ; and, indeed, we can more 

 readily admire than imitate their untaught art and sapience. 



EXERCISE THE THIRD. 



Of the upper part of the hen's uterus, or the ovary. 



The uterus of the fowl is divided by Fabricius into the superior 

 and inferior portions, and the superior portion he calls the ovary. 



The ovary is situated immediately beneath the liver, close to 

 the spine, over the descending aorta. In this situation, in the 

 larger animals with red blood, the coeliac artery enters the me- 

 sentery, at the origin, namely, of the emulgent veins, or a little 

 lower ; in the situation moreover in which in the other red- 

 blooded and viviparous animals the vasa praeparantia, tending 

 to the testes, take their origin : in the same place at which the 

 testes of the cock -bird are situated, there is the ovary of the hen 

 discovered. For some animals carry their testicles externally ; 

 others have them within the body, in the loins, in the space 

 midway from the origins of the vasa praeparantia. But the 

 cock has his testicles at the very origin of these vessels, as if his 

 spermatic fluid needed no preparation. 



Aristotle 1 says that the ovum begins at the diaphragm ; " I, 

 however/' says Fabricius, " in my treatise on Respiration, have 



1 Hist. Anim. lib. vi, c. 2. 



