462 MONTGOMERY. [Vol. XV. 



stain in the same manner as those contained in the cytoplasm. 

 But occasionally from one to three of the larger globules (Fig. 

 267) in the nucleus stain much more intensely than the others, 

 though intermediate degrees of staining are to be found between 

 these largest, most deeply colored ones and the smaller, less 

 deeply stained ones ; so that there can be no doubt of the 

 genetic relation of the two kinds. By staining with eosin 

 these largest yolk globules in the nucleus stain almost or quite 

 as deeply as the nucleolus itself, so that at first I mistook them 

 for nucleoli ; but that they are chemically metamorphosed yolk 

 globules and not nucleoli is shown, even leaving aside the fact 

 that all intermediate forms may be found between them and 

 the less deeply staining globules of the cytoplasm, by the fact 

 that vacuoles are never found within them. By the Ehrlich- 

 Biondi staining method no color differentiation was to be 

 obtained for the larger and smaller yolk globules of the nucleus. 

 But nevertheless I would think that these large yolk globules 

 (or accumulations of such globules) which have been taken 

 into the nucleus from the cytoplasm and there have undergone 

 some degree of chemical change, possibly stand in genetic 

 connection with that body which is apposed to the nucleolus 

 in the larger germinal vesicles, and which has been described 

 in the preceding paragraph. 



Chromatin. — We found the chromatin in the primitive peri- 

 toneal cells and in the youngest ovogonia to be arranged in the 

 form of granules (Figs. 250-254). In the following mitoses it 

 is arranged in the form of a spirem, then of chromosomes, and 

 again of a spirem (Figs. 255-261). Just after the conclusion 

 of the spirem stage (of the metaphasis) it comes to lie in a 

 more or less dense mass around the nucleolus, this mass 

 appearing to be composed of a reticulum of short fibers (Figs. 

 263-266, 270, 271, 278). In all these stages the chromatin is 

 marked by its deep blue staining with haematoxylin. After 

 the last stage described it gradually departs from the close 

 vicinity of ^ the nucleolus and becomes evenly distributed 

 throughout the nucleus. But when it has thus become diffused 

 it does not stain with haematoxylin as before, but appears in 

 the form of a very large number of minute microsomes, which 



