FOODS N U TRTTION . 705 



"The feeding of simple proteids — syntonin, casein, and its sodium salts — failed to 

 yield an increase of glycogen in the liver when a single dose was given. But after 

 trials lasting several days, during which considerable quantities of casein were 

 ingested, an accumulation of glycogen too large to be attributed to any residual store 

 in the liver was repeatedly found. ... It has already been pointed out that nega- 

 tive results in experiments like the present ones do not necessarily indicate the 

 incapacity of the substances fed to promote glycogen formation." 



The author discusses the possibilty of leucins being the important intermediate 

 bodies in the formation of sugar and glycogen in the body from carbohydrate-free 

 proteids, and notes that the 2 experiments, which he reports, "do not, at least, 

 speak against the possibility under discussion; nor do they justify any far-reaching 

 statements. The physiologist must look forward to a more profound acquaintance 

 with the chemistry of the proteid molecule before the final word can be spoken." 



On the formation of dextrose in metabolism from the end products of a 

 pancreatic digest of meat, P. G. Stiles and G. Lusk {Arncr.Jour. Physiol., 9 {1903), 

 Xu. 6, pp. SSO-SS-')). — Tests are reported in which dogs were given the product 

 obtained by the pancreatic digestion of washed meat. The digestion was continued 

 for 14 months with i:)roper precautions against putrefaction, and tlie result was 

 described as a dark sirupy fluid, with but little sediment or suspended matter, con- 

 taining 1.33 per cent nitrogen and giving only a doubtful biuret reaction. "The 

 taste and odor were pronounced but not foul." It was found that 5 gm. of nitrogen 

 fed in the form of these pancreas digestion products, according to the authors, may 

 give rise to the formation of about 12 gm. of dextrose. 



" The same amount of nitrogen fed as native jiroteid would be expected to produce 

 18 to 19 gm. of sugar. No light is thrown upon the question whether the sugar in 

 our experiments was formed after a proteid synthesis had occurred or more directly 

 from the amido-bodies. Neither have we any evidence as to the relative importance 

 of the several digestive products which were fed. . . . The experiment shows that 

 it is impossible for a large sugar radical to exist in the proteid molecule. The amido 

 nitrogen fed was quantitatively eliminated, and did not protect the body's proteid as 

 do meat and gelatin under similar circumstances." 



Salivary digestion in the stomach, W. B. Caxnox and H. F. Day {Amcr. Jour. 

 PIq/siol., 9 {1903), No. 6, pp. 396-416). — Experiments reported on salivary digestion 

 in the stomach were carried on with cats, the authors' earlier investigations having 

 shown that, like the stomach of the dog, rat, rabbit, guinea \ng, and man, the stom- 

 ach of the cat is separated into 2 parts — the quiet cardiac end and the active pyloric 

 end. The animals were fed powdered crackers mixed with a uniform amount of 

 filtered human saliva, and after the expiration of from one-half to 2 hours were 

 etherized, killed, and the stomach contents examined, care being taken to keep the 

 material in the cardiac and pyloric portions separate. 



From the results of their experiments the authors believe that the commonly 

 accepted idea that the action of ptyalin is inhibited soon after the ingestion of food 

 is not conclusively proved, and that there is little or no warrant for the commonly 

 accepted accounts of mixing currents in the stomach. Observations show that in 

 many animals, including man, gastric peristalsis occurs only in the pyloric end of 

 the stomach; the cardiac end remains undisturbed by the waves. Food in the 

 pyloric end is soon mixed with the gastric secretions, but food in the cardiac end of 

 the stomach is not mixed with the acid gastric juices for 2 hours or more, and in this 

 region, therefore, during that time salivary digestion may go on undisturbed. 



In experiments with cats it appeared "that the percentage of sugar present is 

 about the same in the 2 portions at the end of a half hour, and at the end of an hour 

 the cardiac portion contains about 80 per cent more sugar in unit volumes than the 

 l)yloric portion. The actual amount of sugar i)resent in tlie fundus is relatively 



