GERM CELLS IN THE ARTHROPODA 123 
It seems highly probable that the ‘‘anello croma- 
tico”’ of Giardina consists of chromatin, and Gold- 
schmidt (1904) and others do not hesitate to class 
it as an example of a “‘ Chromidialapparat.”’ Further- 
more it is apparently the result of a chromatin- 
diminution, as Boveri (1904) maintains, differing 
from the similar process in Ascaris and Muastor in 
details but not in the ultimate result. Finally, the 
discovery of this peculiar body in Dytiscus adds one 
more argument to the hypothesis that the chromatin 
content of the germ cells differs from that of the 
somatic cells quantitatively, at least in some cases, 
and perhaps also qualitatively. 
Many are the bodies that have been homologized 
with the “anello cromatico” of Dytiscus. Buchner 
(1909) claims that the nucleolar-like structure in 
the odgonia and young odcytes of Gryllus is homol- 
ogous to both accessory chromosomes of the sper- 
matogenesis and to this chromatin ring in Dytiscus. 
This “ accessorische Kérper”’ passes intact into one 
half of the odcytes where it disintegrates into granules 
of a “tropische Natur.”” Foot and Strobell (1911) 
have also compared it with the chromatin nucleolus 
in the odgonia of Protenor with which it has certain 
characteristics in common, but no such differential 
divisions occur as in Dyftiscus. 
Govaerts (1913) was unable to find anything 
resembling the chromatic ring of Giardina, and con- 
cludes that the formation of a chromatic mass dif- 
ferentiating the odcytes and the nurse cells is unique 
in the Dytiscip™. His investigations demonstrate 
