No. 560] INFLUENCE OF FASTING ON GROWTH 481 



The animals were weighed both before and immediately 

 after feeding, so that the amount of food consumed could 

 be ascertained accurately by subtracting the former 

 weight from the latter. After twenty-four hours the 

 animals were weighed again, the difference between this 

 weight and that of the previous day giving the growth for 

 twenty-four hours. In some cases the increase is only a 

 fraction of the quantity of food which the animals re- 

 ceived; not infrequently, however, it has been even 

 greater than that quantity. In the case of the four sala- 

 manders recorded above there are ten out of eighteen 

 determinations, which show an excess of growth over the 

 amount of ingested food. We find that the coefficient of 

 growth never falls below 0.5 (the one instance where it is 

 only 0.24 is obviously accidental) ; in other words, as re- 

 gards weight the increase of the body is never equal to 

 less than one half of the quantity of ingested material, 

 and the average coefficient for all four animals for a 

 seven-day period of renewed feeding is 0.73. This fact 

 is particularly significant when we compare it with the 

 condition found in continually fed specimens. In the 

 case of other four control salamanders it was found that 

 the coefficient of growth was only 0.26, i. e., only about 

 26 per cent, of the food had gone to the building up of the 

 body substance. 



When the growth occasioned by a return to a normal 

 diet after a protracted starvation is studied from the 

 point of view of the body dimensions instead of the body 

 weight, it appears that it is exceedingly slow during the 

 first two weeks, showing that during that time primarily 

 the internal organs undergo reparation, the enlargement 

 of the musculature and of the skeleton ensuing sub- 

 sequently. 



Salamanders fed intermittently did not become as 

 heavy nor as large as the control specimens; that is to 

 say, their growth has been retarded from the point of 

 view of both weight and size. The coincidence of the 

 results of measuring both weight and length of the body 



