No. I.] SPERMATOGENESIS OF BATRACHOSEPS. 55 



be counted. The daughter-cells resulting from these polymor- 

 phous spermatogonia are of oval form, which probably is due to 

 their great number and to the small space into which they are 

 crowded, and also to their rapid increase in size. After a 

 period of growth these daughter-nuclei, as well as the whole 

 cell, resemble almost exactly the cells of the imperfect resting 

 stage of the polymorphous spermatogonia, and a description of 

 one kind would also fit the other. The nucleus is round or 

 oval, with a very distinct membrane. 



The largest part of the nucleus is taken up by an evenly 

 distributed but not quite regular network, consisting of very 

 small chromomeres or of isolated chromioles suspended in 

 and supported by a linin meshwork (Figs. 9, 19), In this 

 meshwork, or rather in connection with it, we find from 

 two to five chromoplasts, rarely more or less. In deeply 

 stained sections we also see several linoplasts of various sizes 

 but generally smaller than the chromoplasts. The cytosome 

 or strictly cellular part is always smaller than the nucleus and 

 cone-shaped, with the base of the cone resting on the nucleus. 

 In this cone is seen a round sphere of about the size of a chro- 

 moplast. It is always stained intenser than any other part of 

 the cytosome ; it appears also to have a great afifinity for the 

 Congo stain. Around this inner or granosphere is seen a much 

 lighter colored zone of more irregular form — the plasmosphere. 

 Surrounding these two spheres is generally seen a narrow zone 

 of fibrous cytoplasm proper. Either in the center of or in the 

 immediate vicinity of the granosphere is seen a minute dark- 

 staining body — the archosome. The archosome generally con- 

 tains two distinct centrioles, though often there are more than 

 two. In rare instances we also find in the plasmosphere an 

 accessory archosome. 



The mitosis of the polymorphous cells is less favorable for 

 observation than that of the two maturation cells, not only on 

 account of the greater number of chromosomes, but also on 

 account of the crowding of the cells, which prevents their 

 proper expansion. The daughter-cells pass through a stage of 

 growth, at the end of which they enter upon the first matura- 

 tion mitosis. The latter will here be referred to as auxocytes. 



