FOODS HUMAN NUTRITION. 471 



stroyed than pepsin ; and tliat the shaking produced by the resi)iratory move- 

 ments is capable of causing some destruction of the ferments. Recent experi- 

 ments by other investigators show also that other ferments may be inactivated 

 by shaking. . . . 



" The assumption is here made that the nature of the destruction of ferments 

 is similar to tliat which takes place in the destruction of living cells, and tliat 

 shaking affects a certain structure whicli is common to living cells as well as 

 to red blood cori)Uscles and to ferments." 



In experiments on the effects of respiratory movements, ferments in rubber 

 or glass containers of suitable construction were introduced into the stomach 

 and peritoneal cavity, a dog and rabbits serving as subjects. 



Nuclein synthesis in the animal hody, E. V. ]McCoLLT:>f (Amrr. .hntr. 

 P/(//.sjo/., 25 (li)OO), A'o. 3, pp. 120-lJfl). — Normal and special rations were used 

 in these experimental studies which were made with rats as subjects. In the 

 author's opinion the recorded data seem to warrant the following conclusions: 



"The palatability of the ration is a most important factor in animal nutri- 

 tion. Without palatability the ration may possess all the necessary food ingre- 

 dients and yet fail to properly nourish an animal. The failure of previous 

 efforts to maintain animals on a mixture of relatively pure proximate constitu- 

 ents of our foodstuffs was due to the lack of palatability of such mixtui'es. 

 When sufficient care is given to changing the character and tlavor of the food 

 supplied in such simple mixtures, it is possible to induce an api)reciab]e amount 

 of growth, ^'ery young animals adapt themselves to a ration possessing a low 

 degree of palataitility much better than do adults. 



" Other things being satisfactory, all the phosphorus needed by an animal, 

 for skeleton, nuclein, or r>hosphatid formation, can be drawn from inorganic 

 phosphates. 



" The animal has the power to synthesize the purin bases necessary for its 

 nuclein formation from some comiilexes contained in the protein molecule, and 

 does not necessarily use purin bases of exogenous origin for this purpose." 



The neurocytological reaction in muscular exertion. — I, Preliminary 

 communication. The sequence of the immediate changes in the Purkinje 

 cells, D. H. DoLLEY (Amci: Jour. PIiy.sioL. 23 (l!)0!)), No. 3. pp. 151-111. plff. 

 2). — In experiments with dogs exercised in a treadmill, studies of the cere- 

 bella showed that physiological activity in nerve cells " results in a definite 

 and consecutive sequence of events whicli are the morphological expressifms 

 of the abstract terms activity, fatigue, and exhaustion." According to the 

 author, the interpretation of the various types of cells and their division into 

 stages is based primarily upon theories of the size relations of nucleus and 

 cell body and of their interdependence as regards a mutual interchange of mate- 

 rial, and upon the extension of the doctrine of chromidial apparatus to nerve 

 cells. 



As the result of continued activity, there is first a steady increase of the 

 l)asic chromatic material, then a decrease until " there results a functionally 

 exhausted cell entirely devoid of basic chromatin." The different stages iu 

 this process are described. 



"The setpience of events is exactly identical with that previously described 

 for anemia and shock, and the reaction to purely physiological states corrob- 

 orates the opinion advanced that the changes in these conditions are a mani- 

 festation of functional activity and represent ])hases of fatigue am] exhaustion,' 



