KEIMBAHN-DETERMINANTS 223 
as such in the cytoplasm for a considerable period. 
It is also possible that, as Buchner (1910) maintains, 
the keimbahn-determinants may be in reality ‘‘ Keim- 
bahnchromidien.” 
This view was suggested by the writer in 1909 
(p. 274) to account for the origin of the pole-disc 
granules in the eggs of chrysomelid beetles. It was 
thought that here as in the Hymenoptera (Bloch- 
mann, 1886; et al.) chromatin granules might be 
cast out of the nuclei of the odcytes, and that these 
granules might gather at the posterior end to form 
the pole-disc. It was also suggested that chromatin 
granules from the nurse-cell nuclei might make their 
way into the odcyte and later become the granules of 
the pole-disc. It should not be forgotten, moreover, 
that these granules stain like chromatin. Finally, 
mention should be made of the “anello cromatico” 
of Giardina (1901) which is associated with the 
differentiation of the odcytes in Dytiscus (see p. 120, 
Fig. 38), and the keimbahn-chromatin which I have 
recently described (Hegner, 19146) in the eggs of 
the parasitic hymenopteron, Copidosoma (p. 151, 
Figs. 46-47). 
Conciusion. Certain keimbahn-determinants 
may consist of nucleolar material which is derived 
from the germinal vesicle and persists until the 
primordial germ cells are established. In some cases 
the keimbahn cells are characterized by the posses- 
sion of the complete amount of chromatin in con- 
trast to the somatic cells which lose a part of this 
substance. Since, however, the chromatin-diminu- 
