368 LOUIS MAX HICKERNELL. 



nuclei, made up of the chromatic ring, with central clear space,, 

 are scattered irregularly about. The densely staining granules 

 of food material, so prominent in the sections of the undried 

 stomach, are not present here. I have examined large numbers 

 of sections of dried animals, and while the food granules are not 

 always entirely absent, as figured here, yet they are absent in 

 many cases, and certainly in all cases they are much less numer- 

 ous than in sections of the stomach of undried animals. This 

 point is of importance as bearing upon the question of meta- 

 bolism in the dried state. As was previously stated, the identity 

 of these granules as particles of food material can hardly be 

 questioned. Zelinka ('88) has called attention to the fact that 

 they do not appear in sections of the stomach of the newly 

 hatched rotifers. Beauchamp ('09) has shown that in sections 

 of the stomach of Hydatina senta which had been feeding regu- 

 larly these granules w r ere present in great numbers, but in sec- 

 tions of the stomach of starved individuals they do not appear. 

 Many authors have commented upon the fact that among those 

 rotifers which survive desiccation the stomach tissue in gross 

 appearance is generally lighter in color after recovery than it 

 was before drying commenced. This observation I have re- 

 peated many times and find it to be correct. I have not, how- 

 ever, been able to find in the literature figures of actual sections 

 of the stomach of rotifers recovering from desiccation. Fig. 16, 

 which is but one of many that I might show, by the absence of 

 all food particles demonstrates that metabolic or at least kata- 

 bolic activities must go on in the stomach tissue of the dried 

 animal. 



Of great importance in connection with the question of the 

 nuclear changes is the determination of the exact time at which 

 the chromatic rearrangement takes place. It is a reasonable 

 supposition that it could not easily be brought about while the 

 moisture is entirely absent from the tissues. Since the proto- 

 plasm is always more or less fluid in nature in its normal con- 

 dition, the changes described would certainly have to take place 

 very slowly if they occurred in the dried state. It would seem, 

 upon theoretical grounds, that the more favorable time for the 

 changes to take place would be during the short period just 



