238 
SIDNEY I. KORNHAUSER 
Many testes show a central core of heterogeneous material 
made up of degenerating cysts. This looks much like the stream 
of food seen passing from the terminal chamber to the growing 
oocytes of telotrophic insect ovarioles. It is not the purpose 
of the present paper to describe the details of the spermatogenesis 
or the cytology of degeneration, although the author hopes to 
attack these questions at another time. 
The ovaries are composed of very long, and much attenuated 
tubules, each fastened at its narrow, cephalic end by a terminal 
filament reaching to the dorsal body wall. The sheath of each 
ovariole is composed largely of tracheal tubules, and undergoes 
rhythmic pulsations. The space between the egg string and this 
sheath is filled with a coagulable fluid. The cephalic tip of each 
ovariole, just caudad to the attachment of the terminal filament, 
is occupied by a Keimpolster; then follow oogonia, showing an 
occasional mitosis ; while a trifle more caudad one may find pairs 
of oogonia both in the same mitotic phase. About one-tenth of a 
millimeter from the Keimpolster occur the ultimate oogonial 
mitoses. Here four cells all in the same stage of mitosis may be 
found, and each cell gives rise to an oocyte and a nurse cell which 
continue in close connection and accompany each other from 
this time until the end of the growth period. Syndesis occurs 
immediately after the differential mitosis, the oocyte here out- 
stripping its sister nurse cell in size. Soon, however, the nurse 
grows much larger than the oocyte, and, at about six-tenths of 
a millimeter from the Keimpolster, they orient in single file 
(oocyte, caudad; nurse cell, cephalad), acquire follicular walls, 
and proceed in the accumulation of yolk material. The large 
nurse cell with irregular nucleus is surpassed finally in size by 
the o5cyte, and becomes a small cap on the cephalic end of the 
ovum. 
5. THE DIPLOID CHROMOSOMES 
A, The female 
Odgonia in their ultimate mitoses show 26 clear, distinct chro- 
mosomes, well separated from one another. Numerous drawings 
• were made and the number 26 established without doubt. Fig- 
