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For ascertaining correctly the form of any stomach, it was found 

 that it should not be distended at the time of the animal's death ; 

 that it should be examined as early as may be after death ; and that 

 its form is best shown by gently distending it with air. 



For the purpose of examining its internal membrane, it should be 

 inverted previous to inflation ; by which means, the folds that are 

 generally observable in that membrane wholly disappear, as they 

 arise merely from its want of contractility, when compared to the 

 more elastic nature of the external coats. 



The stomachs of which Mr. Home has given descriptions, accom- 

 panied with drawings of most of them, are those of the turkey, cod, 

 hare and rabbit ; beaver and dormouse ; the water rat, common rat 

 and mouse ; the horse and ass ; the kanguroo ; the hog, pecari, and 

 elephant; the mole; the stoat and armadillo; together with those of 

 men and of dogs. The circumstances principally noticed in these 

 descriptions are the extent to which the articular lining is carried ; 

 the appearance of the membrane that succeeds its termination ; the 

 situation and forms of any glands that are observable in the several 

 parts of each stomach ; and, more especially, a contraction which in 

 some animals forms a permanent division of the last stomach into two 

 parts, and even mothers, as man, where no such division has been 

 observed. Mr. Home is of opinion, that a similar, though partial, 

 subdivision takes place during life by muscular contraction, as some 

 traces of it may in general be detected after death, if the stomach be 

 examined early and under favourable circumstances. 



From the anatomical structure of the different stomachs described 

 in the present and two preceding papers, Mr. Home is led to consider 

 the functions belonging to the several parts of that organ. 



The cuticular lining of the first, second, and third stomachs of ru- 

 minants has occasioned them to be considered as mere reservoirs ; 

 but since they are supplied with secretions, he thinks that, like those 

 in the crops of birds, they assist in softening the food and in pre- 

 venting fermentation. It appears also, from Dr. Stevens's experi- 

 ments, that even these have somewhat of a solvent power. 



Mr. Home makes a remark that he thinks deserving of notice, re- 

 specting the preparation of food in the first cavity ; namely, that a 

 certain quantity is always retained there, even though the animal 

 has fasted for a whole week previous to its death. 



The digestive process of ruminants he considers as very similar to 

 what takes place in birds with gizzards, who swallow the food with- 

 out mastication. It is then softened in the crop ; after which the 

 gizzard, like the grinders of the ruminant, prepares it for solution 

 and conversion into chyle. 



This general resemblance having led him to a more minute com- 

 parison of their glandular structure, it was observed, that at the en- 

 trance into the gizzard there is a glandular zone that secretes the 

 true gastric juice, having the power of dissolving the food. This so- 

 lution, according to Mr. Home, is the second step in the process of 

 digestion, and is effected in ruminants by the cardiac portion of the 



