No. I.] SPERMATOGENESIS OF BATRACHOSEPS. 39 



granules for the transmission of characters. If, as I suppose, 

 the chromioles constitute these granules, then it is probable 

 that we have to identify the denser protoplasmic mass in the 

 cell of the Cyanophyceae as being chromioles and not cyto- 

 microsomes. In connection with this question it is interesting 

 to note that the nucleus of leucocytes, both in batrachians and 

 in man, contains only a few chromioles. 



The Archosome. 



The Archosome Proper: its Structure, Centrosphere, Somo- 

 sphere, and Centrioles. — As the archosome I designate that 

 particular structure which takes part in the radiosomic process 

 of the cell, and which is situated at the very pole of the spin- 

 dle, at least during certain stages of the mitosis. The archo- 

 some consists of the following parts : One 

 or more interior granules — the centrioles 

 of Boveri. Surrounding them we find a 

 generally very thin zone or sphere — the 

 somosphere. Both the centrioles and the 

 somosphere stain deeply, the centrioles 

 much more so than the somosphere, and 

 it is sometimes difficult to distinguish 



. , , _ , , . An archosome consisting of an 



one from the other. I believe the word outer centrosphere, an inner 



" centrosome " might, with advantage, som°sphere, with two cen- 



° ' Sj » tnoles. 



be retained to designate this inner part 



of the archosome, consisting of centrioles and somosphere. 

 Next outside of the somosphere we find a larger, generally 

 non-stainable, achromatic zone — the centrosphere. This 

 zone is, however, not always achromatic, but takes the stain 

 under certain conditions and stains then with plasma stains. 

 Usually this centrosphere is figured as a round disc, with a 

 perfectly circular outline, giving one the impression of being 

 nothing but a vacuole, in the center of which is situated the 

 centrosome proper. This description of the centrosphere is, 

 however, not quite correct. While the centrosphere is fre- 

 quently circular in outline, it is not always so ; indeed, I 

 think that in the majority of instances it is not circular, but 

 of an amoeboid form. 



