42 EISEN. [Vol. XVII. 



As a result of my observations I have come to the following 

 conclusions in regard to the nature, position, and functions 

 of the archosome. 



The archosome is a specialized accessory archosome, special- 

 ized for the purpose of conducting the radiosomic process of 

 the cell. During the resting stages of the cell the archosome 

 is generally, but not always, situated on the axis of the cell ; 

 during mitosis the archosome is situated at the pole of the cen- 

 tral spindle. The archosome gives rise to the accessory archo- 

 somes by budding, and, vice versa, an accessory archosome may 

 take the function of an archosome. As the archosome is, as a 

 rule, found in the concave part of the granosphere, its peculiar 

 and distinct qualities may depend on some particular food or 

 stimulus furnished by that sphere. 



As regards the functions of the archosome in connection 

 with the spindle fibers, we find that the mantle fibers, as well 

 as the central-spindle fibers, start out from the outer margin of 

 the centrosphere and do not connect with the somosphere or 

 with the centrioles. I have found this to be the case in every 

 instance where I could see the pole of the spindle in a favor- 

 able manner. The fibers or rays are thus not inserted in the 

 somosphere, but simply join the outer surface of the centro- 

 sphere. The only rays which are in actual contact with the 

 somosphere are the contractile fibers, or those fibers which 

 attach themselves to the chromosomes for the purpose of pull- 

 ing them apart. The main part of the contractile fibers starts 

 also from the exterior margin of the centrosphere, but each 

 fiber is seen to be connected with the somosphere by a very 

 thin thread of dark-staining substance (Figs. 110-113). 



In the early resting stage of the polymorphous cells some- 

 times neither archosome nor accessory archosomes can be dis- 

 tinguished. Whether they are at such times situated in the 

 nucleus or are not stainable I am unable to decide upon, but 

 the former seems to me the most probable. In many such 

 resting cells we find one or more darkly staining bodies which, 

 however, are seldom situated in the axis of the cell. As soon, 

 however, as the granosphere has assumed a definite form the 

 two-centrioled archosome is seen to be situated in its center. 



