ON THE DIGESTIVE FUNCTION, ETC. 



U5 



left side, and is the largest of all ; the vulgar name for this is the pauncho 

 There are no wrinkles on its internal surface ; but the food is considerably 

 macerated in it by the force of its muscular coat, and the digestive secre- 

 tions which are poured into it. Yet, in consequence of the vegetable and 

 unanalogous nature of the food, it requires a much fartlier comminution ; 

 and is hence forced up by the esophagus into the mouth, and a second 

 time masticated ; and this constitutes the act called rumination, or chewing 

 the cud. After this process, it is sent down into the second ventricle, for 

 the esophagus opens equally into both, and the animal has a power of di- 

 recting it to which soever it pleases. The ventricle is called the bonnet or 

 king's-hood ; its internal surface contains a number of cells, and resembles 

 a honey-comb ; it macerates the food still farther ; which is then protruded 

 into the third ventricle, that on account of its very numerous folds or wrin- 

 kles, is called many-plies^ and vulgarly many-plus. It is here still farther 

 elaborated, and is then sent into the fourth ventricle, which, on account of 

 its colour, is called the red., and by the French le caille^ or the curdle, 

 since it is here that the milk sucked by calves first assumes a curdled ap- 

 pearance. It is thus that the process of digestion is completed, and it is 

 this compartment that constitutes the true stomach, to which the others 

 are only vestibules. 



There are some animals, however, which do not ruminate, that have 

 more than one stomach ; thus the hampster has two, the kangaroo three, 

 and the sloth not less than four.* Nor does the conformation terminate 

 even with quadrupeds ; for among birds the ostrich has two ventricles,! 

 and among fishes the stomateus Hiafola. The horse and ass, on the con» 

 trary, though graminivorous quadrupeds like the ox, have only one stomach. 



There may seem, perhaps, something playful in this application of dif- 

 ferent systems of mechanism to the same class of animals, and of the same 

 system to different classes : but it shows us, at least, that the hand of nature 

 is not necessarily fettered by its ov/n general laws, nor compelled, even 

 under the same circumstances, to adopt the same cause to produce the 

 same effect. Yet, if we had time, we might proceed beyond this remark, 

 and point out, if I mistake not, the reasons for such diversities, and the 

 skill with which they are introduced. Thus the horse and ass are formed 

 for activity, and require lightness : and hence the bulk and complexity of 

 three or four stomachs would counteract the object for which they are 

 created ; but it does not interfere with the pursuits of the ox, which is 

 heavy and indolent in its nature ; and which, though it may perhaps be em= 

 ployed as a beast of burden, can never be made use of for speed The 

 activity of the horse and ass, moreover, excites, from the stimulus it pro- 

 duces, a larger secretion of gastric juice than is met with m the ox, and 

 thus in a considerable degree supplies a substitute for the thf ee deficient 

 stomachs ; but it by no means extracts the nutriment so entirely from the 

 food introduced into it ; and we hence see the reason why the dung of 

 horses is richer than that of black cattle, and why they require three or four 

 times as much provender. 



We may apply the whole of these remarks to the ostrich, whose pecu- 

 liar habitation is the sandy and burning deserts of the torrid zone, where 

 not a blade of grass is to be seen for hundreds of miles, and where the little 

 food it lights upon must be made the most of. The double stomach it 



* Wiedemaniij .ArchiF. b, i. 



I Valisnieri, Anatomia, he. p. 159. 17I3, 



