618 CAROLINE M. HOLT 



All of these facts suggest that increased metabolism of the 

 older epithehal cells may be a means of supplying needed food 

 material to the developing cells of the adult gut during the pupal 

 changes. That this great increase in the amount of chromatin 

 in cells which have attained their growth, functioned for a time, 

 and are about to be absorbed, is not accidental, or simply a 

 process of degeneration, seems reasonably clear from the uni- 

 formity and universality of this increase in the intestine of Culex. 

 Every cell of the larval gut epithelium apparently passes through 

 the whole series of changes above described before it reaches 

 the stage of disintegration. If this were simply a process of 

 degeneration, it would be hard to account for the tremendous 

 growth in the chromatin material and for the retention of the 

 individuality of the chromosomes to the end. One would expect 

 the processes observed in the disintegration of the cells, to come 

 directly wdthout these elaborate preparatory phenomena. It 

 would seem that we have here, not the hit-or-miss phenomena 

 of degenerating cells, but a definite adaptation to provide for 

 the support of the organism during metamorphosis. 



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