CHROMIDIA AND THE BINUCLEARITY HYPOTHESES. 297 
Lithe, ’?04), and I think it is almost certain, from the recent 
work ot Kuschakewitsch (’07), that Drzewiecki has arrived at 
his results by combining a series of degeneration phenomena. 
At all events, Drzewiecki’s accoent stands in need of confirma- 
tion, and cannot be accepted at present. 
It appeared from the work of Léger (04) and others, that 
the chromidia of gregarines were probably the same sort of 
thing as those of Actinospherium. But the most careful 
recent work—that of Comes (’07)—has put the matter in a 
different hght. Comes studied Stylorhynchus and Steno- 
phora (text-fig. 15). He observed the chromidial changes 
TrxT-FIe. 15. 
A small Stenophora juli, showing deeply stained particles 
(chromidia) in the cytoplasm. (From a borax-carmine pre- 
paration. [ Original. }.) 
which occurred with change of nutrition, temperature and 
season. The important fact brought out by this study is that 
the chromidia are not of nuclear origin—they are metabolic 
products in the cytoplasm. Their part is played in the vege- 
tative life of the organism. In view of these facts it is obvious 
that the chromidia of gregarines require cautious considera- 
tion in relation to the nucleus. 
Before passing to the bacteria, I may here note the nuclear 
apparatus of a very remarkable, and as yet unclassifiable, 
organism—Siedleckia nematoides (Caullery and Mesnil, 
98, °99). I have lately studied this parasite, from a new 
host, Ariciafw@tida. Siedleckia contains small chromatin 
