616 CAROLINE M. HOLT 



series' is consistently present, which could be explained if we 

 were to suppose a difference in initial rhythm between the 

 maternal and paternal elements of each original chromosome pair. 

 If multiple complexes were simply the result of the breaking 

 up of chromosomes in degenerating c ells, then we should expect 

 to find, not simply the multiples of three, but any other number. 

 Neither should we expect to find the chromosomes of uniform 

 size, had they arisen by fragmentation. 



We are led to believe, from the behavior of the chromosomes of 

 these metamorphosing cells, that the three pairs of chromosomes 

 which appear in the original gut cell are made up of quite distinct 

 individuals, differing from each other to such a degree that 

 chromatin split from one can not associate itself with that from 

 another pair. So, all through the series of divisions which precede 

 the final disintegration, we find the daughter chromosomes of 

 each of the original chromosomes maintaining the size and 

 appearance of the original structure ; and moreover, we find each 

 group of daughter chromosomes so closely associated that they 

 behave as a single individual. Chromosome individuality, 

 alone, can account satisfactorily for these conditions. 



In the intestinal cells at least, there is no question of Boveri's 

 Law of cell size being determined by the number of the chromo- 

 somes. A glance at the figures on plate 4 shows conclusively 

 that no such relation exists, nor can the converse be true — that 

 nuclear size is dependent upon amount of cytoplasm. Hert- 

 wig's idea of a definite fixed ratio existing between cytoplasm 

 and nucleus does not hold here. It is true that the intestinal 

 cells increase in size as they approach the time for disintegration, 

 but this would seem to be due to the general acceleration in the 

 metabolic processes, and to have no direct connection \\dth size 

 of nucleus or number of chromosomes. Cytoplasm and nucleus 

 appear to be acting more or less independently. ' Kern-plasma- 

 spannung' could scarcely be the cause for the division in two cells 

 of equal size, of which one has a nucleus of twelve chromosomes 

 and the other forty-eight. In these metamorphosing cells, at 

 least, we must look for a cause for cell division other than the 

 Kern-plasma Relation which is here extremelj^ variable. 



