DALTON G. PAXMAN. 



protoplasm, h, in which no well-defined nucleus is present. How- 

 ever, in this latter case the mass is so close to a nucleate mass that 

 I cannot say positively that it is not continuous with it. 



By closely examining the nuclei present in these masses, I 

 find that the nuclear membranes are very indistinct in many 

 cases. Fig. 2 shows a mass in which the nuclei have indistinct 

 membranes. Also one of the nuclei, c, has a somewhat less 

 distinct membrane than the other, b. And this latter membrane 

 is in turn less distinct than the membranes of the nuclei in the 

 cell syncytium above it. 



Moreover, a large number of nuclei have been seen which 

 lack membranes completely. The nucleus consisted of a 

 "nucleolus" or "karyosome" surrounded by a clear zone. Figs. 



3, 4, and 5 show "karyosomes" which lack membranes. As 

 Child and Young have already suggested, I believe this " nu- 

 cleolus" represents the chromatin material of the nucleus. 



By observing the protoplasm under high magnification (2,000 

 diameters) it is seen that the protoplasmic strands contain many 

 dark staining granules of various sizes and shapes. Some of 

 these granules were as large as the "nucleoli " of the complete 

 nuclei ; others, however, were so small as to be scarcely discernible. 

 Fig. 4 shows a mass which contains a number of varying-sized 

 granules. Fig. 5 shows a mass which contains a number of 

 varying-sized granules one of which, g, is becoming surrounded 

 by a clear zone. 



The protoplasmic masses apparently arise by the outgrowth 

 of protoplasm from certain cells of the syncytium. Figs. 2, 3, 



4, and 6, show masses of protoplasm continuous with the syncytial 

 cells around them. In Fig. 6, the developing mass is very small 

 and contains no definite nucleus. In Figs. 2, 3, and 4, the masses 

 are very large and contain from one to five complete nuclei. 

 A large number of masses have been observed varying in size 

 between these extremes. The nuclear membranes of the nuclei 

 in the cells from which these masses are developing, contain very 

 small, irregular granules which stain darkly like the granules 

 in the cytoplasm. I have insufficient evidence for or against 

 Young's view of the "de novo" origin of these granules. The 

 chromatin granules may arise "de novo" in the cytoplasm and 



