122 
Thos. H. Montgomen’, jr. 
cjuciitly the spevjiiatids and sperraatozoa rcsiilting froin tliem, are much 
larger tlian in the otlier follic-lcs. Tins relation was foimd to be constant 
in all of the 41 testes of Euschistus examined, as well as all 4testes of 
E. iristigmus. This size difference of the cells in the several follicles is 
very striking, and at once apparent with low powers of the microscopc. 
ln certain other Pentatomid genera {Brochjmena, Perilhs, Nezara, Cos- 
mopepla, Momidea, Trichopepla) no such constant size difference was 
fonnd, or it is at least niiich less appreciable. 
The details are as follows in Euschistus sp. 
The sperniatogonia of correspondent generation are of approxima- 
tcly the saine size in all six follicles, as sho^^■Tl in figs. 8 and 16 of PI. IX, 
from the second and tliii-d follicles respectively; the dimegaly does not 
arise until the growth period of the sperniatocytes. This can be definitely 
decided by coinparing actually equivalent stages of cells from different 
follicles. Xow there are two genera tions of sperniatogonia in the adult 
testis, and it is sometimes difficult to distinguish these with certainty, 
but by examining the early synapsis (synizesis) stage of the sperniatocytes 
an exact comparison can be niade, for this stage is immediately recogni- 
zable by the dense condensation of the nuclear chroniatin. Fig. 37, PI. X, 
represents a portion of a longitudinal section tluough parts of follicles 
1 and 2; the septuni is shown down the length of the figure, and to the 
left of it is follicle 1, to the right foUicle 2. It will be seen that the germ 
cells of the synaptic stage, those cells with the massed chromosomes, 
are of approximately equal size in the two follicles. Yet the sperniato- 
cytes of follicle 1 will beconie several tinies larger than those of follicle 2. 
It results from a study of several testes that the dimegaly arises in the 
sperniatocytes after the early synapsis stage, i. e., at the commeiicement 
of the growth period. This positive decision enables us at the sanie time 
to conclude definitely that sjierniatogonia of the sanie generation are of 
the sanie volunie in all the testicular follicles. 
This dimegaly is illustrated in the figures of PI. IX all drawn from 
one testis (no. 282) and to the sanie scale. Sperniatocytes at the end of 
the growth period, which is an approximate if not complcte rest stage, 
are in follicles 1 and 3 (fig. 17, follicle 3) constantly of several tinies the 
volunie of s])ermatocytes in the other follicles (fig. 9, follicle 2; fig. 27, 
follicle 4). Cells at the stage of first maturation spindle are siniilarly 
largest in foUicles 1 (figs. 1—3) and 3 (fig. 18), considerably smaller in the 
other follicles (figs. 10, 11, follicle 2; fig. 30, follicle 5; fig. 34, follicle 6). 
In the sanie way the second sperniatocytes of follicles 1 (figs. 4, ö) and 3 
(figs. 19 — 23) are constantly larger than those of the other follicles (fig. 12 
