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stance during the process of digestion. The other structures seen 

 in the pea are carefully described ; the most curious among them 

 being the cells composing the external layer of the testa, which 

 bear so strong a resemblance to columnar epithelium of the intes- 

 tine, that they might be mistaken for the latter by an inattentive 

 observer. 



The substances submitted to experiment were, 1, boiled wheat- 

 starch ; 2, wheaten bread ; 3, uncooked tous les mois ; 4, boiled 

 tous les mois ; 5, boiled potato ; 6, uncooked peas ; 7, boiled peas ; 

 8, boiled peas after ligature of the bile-duct ; 9, boiled potatoes 

 after ligature of the bile and pancreatic ducts. Several subsidiary 

 experiments were made to determine the action of the intestinal 

 mucus, the saliva, and the substance of the pancreas, on starch. 



The conclusions at which the author arrives from the experiments 

 are, 



1 . That the starch-granule is composed of two parts, chemically 

 and histologically distinct, a cell-membrane and homogeneous 

 contents. The markings seen on many varieties of starch are re- 

 ferred to folds or markings of the investing membrane. 



2. No perceptible change occurs in the starch, whether raw or 

 cooked, during its sojourn in the stomach of quadrupeds or the 

 ventriculus succenturiatus and gizzard of birds ; all the granules 

 preserve their perfect reaction with iodine and their pristine ap- 

 pearance. 



3. The conversion of boiled starch into dextrine and glucose is 

 chiefly effected in the first few inches of the small intestine, but it 

 continues to take place in a less degree throughout the entire intes- 

 tinal canal. 



4. In the digestion of boiled wheat or other starch, or of wheaten 

 bread, the bulk of the mass rapidly diminishes in its passage through 

 the small and large intestines, so that it ultimately yields only a 

 small quantity of faecal matter. After being deprived of their con- 

 tents, the membranes of the granules shrink and shrivel up into a 

 minute granular matter, which constitutes the chief bulk of the 

 faecal evacuations after an exclusive diet of starch food. 



5. The digestion of raw starch food (peas) in the pigeon or other 

 granivorous birds goes on much more slowly, and progresses pretty 

 equally throughout the entire intestinal canal. The starch-granules, 



