492 E. ELEANOR CAROTHERS 
Figure 11 represents an early secondary spermatogonium and | 
is of especial interest on account of the loop shown at c. The 
dense granules at both ends of the dyads are very evident. This 
is a peculiarity that marks certain chromosomes as was noted by 
Miss Pinney (08, p. 318). The curve of the free and of the 
longer dyad of the unequal tetrad (fig. 19 c) had long puzzled me, 
but in view of the earlier relation of these elements shown in 
figure 11 ¢ it is evidently due to the separation, at this point, of 
the dyads which had previously been united at both ends. Dur- 
ing the growth period this tetrad is associated with the accessory 
both in Arphia and Brachystola. This is probably merely a per- 
sistence of the conditions established at the formation of the com- 
posite granule. When the accessory breaks away from this body 
it carries with it several granules with their chromatin threads! 
—in Brachystola, for a time, forming a conspicuous second center 
of radiation. Figure 25 shows all three small chromosomes still 
adhering to it, but the relation with the unequal tetrad is the 
most persistent. Figures 18, 18 e and 19 are successive stages in 
Arphia. Figure 17 is from Brachystola. 
3. First spermatocytes 
Brachystola. As soon as the chromosomes have become suffi- 
ciently condensed to be recognized as distinct individuals, the 
accessory, which at first is in the form of a ‘U’ with the arms ap- 
proximated, is often seen connected with a small chromosome 
more dense than any of the others, except the accessory itself 
(fig. 24). There are at this time eleven individuals, counting 
the multiple as one (fig. 28). The larger dyad of this tetrad 
shows a transverse constriction, giving the whole a tripartite 
appearance. Either the larger or smaller end may be attached 
to the accessory (figs. 23 and 24. 
In early metaphases the chromosomes appear as twelve separate 
individuals. Side views show the accessory in its characteristic 
position near one pole. The smallest chromosome frequently 
shows a constriction; the next in size rarely gives an indication of 
approaching division, while the third is entirely separated, only a 
1 This was first noted by Wenrich who also suggested the term ‘composite granule.’ 
