94. BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
trace the pair through all the stages from the spermatogonia to the 
spermatids, thus constituting a demonstration of a case of continuous 
identity, or individuality, through these stages. It was also possible 
to recognize chromosome-pairs B and C in the spermatogonial telo- 
phases as well as in the second spermatocytes and spermatids. 
8. In the earlier pachytene stages, chromosome-pair B was found 
to have a definite arrangement of granules or chromomeres, and it was 
shown that the relative sizes and positions of these chromomeres re- 
mained constant for similar stages, not only in different cells of a 
single individual, but also in all the thirteen animals. 
9. The spermatogonial divisions showed that each chromosome 
forms a sac or vesicle in the earlier telophases, and that it expands 
and becomes diffused within these vesicles; that, although the vesicles 
appear to coalesce, there is always a remnant of each chromosome 
visible in the center of the region occupied by the vesicle, and that in 
the prophase the chromatin concentrates about this remnant or core 
and there forms a spirally coiled thread, which develops into a prophase 
chromosome. 
10. Study of somatic cells showed: — (1) that chromosome B 
could be recognized in the connective-tissue cells within the follicle, 
and (2) that cells of the follicular envelope, which are probably in a 
state of senescence, still preserved the normal number (23) of chromatic 
masses. 
11. The polar granules are constant features of the organization 
of the individual chromosomes, as was shown by Pinney (’08); but 
in some cases (chromosome-pairs A and B) they may become modified 
to give rise to expansions which resemble the “ vesicles”? described by 
Carothers (’13), as well as the “plasmosomes”’ of most authors. The 
polar granules tend to unite into composite granules at all of the diffuse 
stages of chromatic evolution. 
12. The accessory chromosome behaves in the manner that is 
typical for the Acrididae. It forms a large separate sac or vesicle in 
the earlier spermatogonial generations and a peripheral compact mass 
in the telophase of the last spermatogonial division. During the 
leptotene and zygotene stages it may unravel into a long loop, which 
in some cases is equal in length to a great circle of the nucleus. In the 
pachytene stages it reassumes a compact form, but may b> attached 
by its polar granule to the polar granules of other chromosomes and 
thus become attached to a composite granule. It passes to one pole 
undivided in the first maturation division but divides in the second. 
