228 O. C. GLASER. 



smaller than a, is also bilobed, and the lobes contain different 

 sized nucleoli. 2? appears to differ from a in three striking details : 

 the finely divided chromatin is not arranged in a reticulum ; there 

 are no larger chromatin bodies and the nucleoli are surrounded 

 by large clear areas devoid of tingible material. The remaining 

 nuclei and their cells (c, d, e,f), illustrate the conditions most 

 commonly met with in the disintegrating cells. The cell con- 

 tents, irregular masses of granules and what appear to be fibrils 

 or strands, are crowded along the inner surfaces of the cell 

 membranes and are separated by clear regions from the bilobed 

 or dividing nuclei that occupy approximately the centers of the 

 cells. These nuclei differ markedly in several respects from 

 those already described. Their granular contents are not clearly 

 reticulate ; such large masses of chromatin as they contain are 

 much condensed and the nucleoli often have definite chromatin 

 radiations, a condition suggesting that all of these nucleoli are 

 chromatin nucleoli, especially as b shows no other large chromatin 

 bodies. In addition large vacuoles are often found inside of the 

 nuclei. 



The direct divisions to which I have devoted most of my atten- 

 tion occur in those regions of the entoderm where neither liver 

 nor disintegrating cells are found. The nuclei there (Fig. 7) are 

 not remarkable for size, in fact they are rather small, a condition 

 which favors the view that they are not very active metabolically. 

 They may or may not exhibit nucleoli, and these may or may 

 not be surrounded by halos devoid of chromatic material. The 

 nucleoli are usually small and their staining reaction is different 

 from that of the other nuclear contents. The chromatin is usually 

 scattered irregularly in the form of granules somewhat larger 

 than those of the other amitotic entodermal nuclei. Some of 

 the nuclei show clear spaces independent of the nucleoli, but 

 these regions of achromatic material are not always sufficiently 

 distinct to warrant the same interpretation for all. Some seem 

 to be vacuolar ; others are certainly not. Many of the nuclei 

 contain two nucleoli. These may differ in size, and may lie 

 rather close together or be separated by a considerable distance. 

 I have never seen such nucleoli in the act of division. Among 

 these nuclei I have found what I interpret as all possible stages 



