102 ANIMAL FUNCTIONS. 



is the natural position. From this central sack, there 

 proceeds ten prolongatives, or canals, which occupy in 

 pairs, the centre of each ray, or division of the body, of 

 which there are five to each star-fish. These prolonga- 

 tions, or stomach subdivide into numerous ramifications 

 on each side, as shown by Fig. 71, c c, which represents 

 one ray of the Asteria, laid open from the upper side. 

 Each ray has two stomachs, such as are here shown, 

 making ten for every animal. 



Increased complexity in the Stomach of the higher 

 orders. We shall not consider it necessary to describe 

 the apparatus for digestion belonging to the different 

 grades of animals as they ascend in the scale of organi- 

 zation. It will be sufficient for our purpose to state 

 that the operations preparatory to the introduction of 

 food into the stomach, increase in some proportion to 

 the complexity of the animal organization. Thus the 

 hydra takes its food into the stomach in precisely the 

 same state >that it happens to come to the mouth, and 

 the fish, snake, frog, and many other tribes swallow their 

 aliment in an entire state. Neither have the birds any 

 organs for mastication, so that in common w r ith them, 

 they take their food in an undivided state. But the 

 birds are furnished with an apparatus for grinding the 

 materials thus swallowed, before they are introduced 

 into the stomach, thus affording an example of com- 

 plexity in the organs of nutritition, proportionate to the 

 general scale of organic developement which these ani- 

 mals exhibit. In all the warm blooded quadrupeds, the 

 food is prepared by mastication and admixture with 

 saliva, before its introduction into the stomach. With 

 the exception of man, all animals take their food in the 

 raw, or natural state ; but with him great preparations, 

 and often very pernicious ones, are made to suit the 

 aliment to his pampered taste r before the act of masti- 

 cation commences. 



Man eats nearly every digestible thing. Man being 

 an all-eating animal, there hardly exists an article which 

 can be digested, in the sea, on the land, or in the air, that 

 he has not in some way or other contrived to render 



