INTRODUCTION. 3 



occasion for a shoulder so vigorously organised as 

 that of carnivorous animals ; owing to which they have 

 no clavicles, and their shoulder-blades are proportionally 

 narrow. Having also no occasion to turn their fore- 

 arms, their radius is joined by ossification to the ulna, or 

 is at least articulated by gynglymus with the humerus. 

 Their food being entirely herbaceous, requires teeth 

 with flat surfaces, on purpose to bruise the seeds and 

 plants on which they feed. For this purpose, also, 

 these surfaces require to be unequal, and are, conse- 

 quently, composed of alternate perpendicular layers 

 of enamel and softer bone. Teeth of this structure 

 necessarily require horizontal motions to enable them to 

 triturate, or grind down the herbaceous food ; and ac- 

 cordingly the condyles of the jaw could not be formed 

 into such confined joints as in the carnivorous animals, 

 but must have a flattened form, correspondent to sockets 

 in the temporal bones. The depressions, also, of the 

 temporal bones, having smaller muscles to contain, are 

 narrower and not so deep ; and so on, throughout the 

 whole organisation. 



The digestive system of the ruminantia is more 

 complicated in structure than that of any other class of 

 animals; and, owing to this complexity, and the con- 

 sequent difficulty of investigating it, its nature and 

 functions have been less perfectly understood. 



The stomach of the Manilla Buffalo, which will serve 

 as an example of all the other species, is divided into 

 four cavities or ventricles, which are usually (but im- 

 properly) considered as four distinct stomachs. 



