20 PAULINE H. DEDERER 
e. Degenerating cells in the ovary 
Groups of degenerating cells are to be found in almost all of 
the ovaries examined, occurring chiefly in the region of the 
tetrads. Similar cells were also noted in the spireme region, 
but very rarely in the egg strings. These cells have the form 
of clear vesicles which contain one or more deep-staining spheres 
of chromatin material. A number of writers have noted this 
condition both in oogenesis and in spermatogenesis. 
No cases of amitosis were observed in any of the germ cells. 
The nurse cells do not divide in any manner after the last oogonial 
divisions, nor do the egg cells, until the maturation divisions. 
f. Abnormal nuclei in the early ovary 
Certain abnormal conditions were observed in nurse cells of 
Stage g. In two ovaries, several cells showed, instead of 13 
bipartite rods, from 15 to 19 rods. These differed further in 
the fact that no longitudinal split was evident. As it hap- 
pened that these two ovaries were the first ones examined, the 
problem was very puzzling, for it appeared to indicate that the 
chromosomes were not of the reduced number. Normal nuclei, 
however, were found in the same material, and sections of about 
40 other ovaries failed to show any abnormal cells. Doncaster 
(12) mentions a somewhat similar abnormality, in which one 
cell showed the diploid, instead of the haploid number of chromatic 
threads. 
2. CONCLUSIONS AND COMPARISONS 
Differential divisions in the oogonia, which have been described 
for the Dytiscidae, are not found in P. cynthia. The germ 
cells all appear similar in size until the post-synaptic spireme 
stage, agreeing in this respect with Pieris and Abraxas’ (Griin- 
berg ’03, Doncaster ’12), the bee (Pauleke ’00), and the dragon-fly 
(MeGill ’06, Marshall ’07): Doncaster finds a differentiation 
appearing a little later than in P. cynthia, when the chroma- 
tin threads shorten to form bipartite chromosomes in the nurse 
