200 CYTOLOGY chap, vi 



(3) The Relation between Chromidia and Chondriosomes 



This last supposed characteristic of the chondriosomes obviously 

 raises at once the question whether these bodies are not the same as 

 chromidia, and here we are once again face to face with a controversy 

 which must at present be left undecided. There can be no doubt that 

 in certain specific cases the same thing has been described by one worker 

 as chondriosomes and by another worker as chromidia — we may compare 

 Fig. 29, D, and Fig. 81, E, both representing the primary spermatocyte 

 of Blatta germanica. We have indeed all possible views of the relation 

 between the two structures supported by different workers. 



(i) Chondriosomes have no relation with chromidia, though in some 

 cases they have been erroneously described as such (Meves, Duesberg). 



(2) Chondriosome is simply a name given to chromidia by those who 

 have failed to recognize their true origin from the nucleus (Goldschraidt, 

 Popoff, Buchner). 



(3) Chondriosomes and chromidia are independent bodies, found side 

 by side in the cytoplasm, the one of cytoplasmic, the other of nuclear 

 origin (Schaxel, Jorgensen). 



Finally, it should be mentioned that both chondriosomes and 

 chromidia have been interpreted in some cases as metamorphosed parts 

 of the achromatic figure. This applies to certain of the very diverse 

 bodies known under the comprehensiv^e terms of " Nebenkern " and 

 yolk nucleus, but it appears certain that most of the structures described 

 as chondriosomes and chromidia cannot be so explained. 



