206 CORA J. BECKWITH 



F. THE NATURE OF THE PROTOPLASMIC GRANULES 



Because of the theoretical interest connected with this question, 

 it is essential to determine, if possible, whether the extra-nuclear 

 granules are chromatin, extruded from the nucleus as such, or 

 whether they are of protoplasmic origin. Certainly, the first 

 impression given by these granules, staining intensely in basic 

 dyes, favors the conclusion urged by Schaxel, that they are chro- 

 matin sent into the protoplasm. The picture is so striking that 

 after many staining tests I was still convinced that such was the 

 case; for all ordinary dyes show identical staining reactions for 

 the granules and the chromatin. It was only after an extended 

 study of the effect of many dyes, both on fixed and living material, 

 that I finally reached a different conclusion, based on the following 

 facts : 



1. The uniform distribution of the basic-staining granules, as 

 described above, makes their direct nuclear origin doubtful. In 

 my material no accumulation of the granules against the nuclear 

 wall, no corresponding accumulation of chromatin-granules 

 within the nucleus, is to be seen at any time. This is especially 

 noticeable in the nucleus of late stages when the basic granules 

 are rapidly increasing, for the nucleus is now uniformly homoge- 

 neous with an affinity for plasma-stains only. 



2. The amount of granular material in Hydractinia can 

 hardly be accounted for if it is all given off in the early growth- 

 period as Schaxel finds in his forms, since this period is of too 

 short duration. An enormous increase in amount takes place 

 after the stage corresponding to Schaxel's 'emission' stage which 

 cannot be explained by simple separation and distribution of 

 pre-existing granules. And since the granules are of the same 

 size in all stages, they cannot be formed by repeated separation 

 without the addition of further material. 



3. If further material is added, there is no evidence that it 

 arises from the nucleus, since at the time when the pseudochroma- 

 tin-granules are increasing rapidly, the nucleus is changing into 

 the so-called resting state, during which time it takes the plasmatic 

 stains while the granules are colored by the nuclear stains. It 



