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IX. On the Gizzards of Grazing Birds. By Everard Home, 
Esq. F.R.S. 
Read April 4, 1810. 
In the course of my enquiries into the various modes in 
which the food in different animals is prepared for digestion, 
many circumstances have been met with, which tend to shew, 
that grass is the substance of all others, on which animals 
feed, that requires the most preparation ; and that ruminating 
animals are fitted by nature in an eminent degree, for extract- 
ing the greatest possible quantity of nourishment from this 
species of food. 
If we examine the means employed by quadrupeds of this 
description, it will appear, that the grass in the first instance 
is broken short off from the ground and swallowed ; then 
macerated with the mass that had previously undergone some 
preparation in the first stomach, and afterwards a part of the 
whole of this mixture, before it is digested, is brought back 
into the motith, there masticated in a particular manner ; not 
as in the elephant and horse, or those nearest allied to them, 
but by being obliquely cut into smaller portions and then 
mixed up with the saliva into pellets, which are conveyed 
through the third stomach into the fourth, for the purpose of 
digestion This is a mode of preparation peculiar to ruminants, 
no other quadruped being provided with all the same means. 
Finding so marked a peculiarity in all the organs connected 
