of the Ardea Argaia, the Casuanus Ejtiu, &c. 81 



In this series of structures, we have not only the gizzard 

 becoming more and more fitted to economize the food as the 

 country becomes less fertile, but we have also an extension 

 of the lower intestines, and caeca, to such a degree as to lead 

 to the belief that the processes carried on in them, render the 

 undigested food subservient to the animal's support. 



MDCCCXIII. M 



