i'REFACE. 



vii 



the predaceous birds or Accipitres the gizzard 

 is wanting; the stomach being more alhed to 

 that of quadrupeds. 



Birds, as every one knows, are oviparous 

 animals, always producing eggs, from wiiich 

 the young are afterwards excluded. The pro- 

 - cess of the young in the egg, from the time 

 of its first production to that of its complete 

 formation, is extremely curious and interest- 

 ing, and may be found detailed with suf- 

 ficient exactness in the works of Malpighi, 

 Buffbn, Monro, and others. I shall only ob- 

 serve on this subject, that the first appearance 

 of the young, as an organized body, begins to 

 be visible in six hours after the egg has been 

 placed in a proper degree of heat; and a 

 particular highly worthy of attention is, that 

 the chick or young bird, when arrived at its 

 full size, and ready for hatching, is by Nature 

 provided with a small, hard, calcareous pro- 

 tuberance at the point or tip of the bill, by 

 which it is enabled the more readily to break 

 the shell, and which falls off some hours after 

 hatching. So careful has Nature been, and 

 so accurately has every circumstance attend- 

 ing the process been foreseen and provided 

 for! 



