438 
Max Morse 
ones, so that tbe number is tbe sarne in botb cases. A greater 
number of cbromosomes tban thirty thvee bas uever beeil counted. 
In tbe group sbown in figure 1, tbe clearness of tbe count is not 
as evident as in the specimen itself, owing to tbe projection by tbe 
camera-lucida of tbe cbromosomes upon one anotber, in some cases, 
wbereas in tbe specimen, these bodies lie at different planes and 
tliey may be readily dissociated by alteration of focus. The char- 
acteristic shape of tbe metaphase cbromosomes is tbat of a slightly 
constricted dumb-bell. Tliere is little Variation in size and shape 
among thern and tliey cannot be paired, two-by-two as is possible in 
otber material. 
In tbe interkinesis between tbe two series of spermatogonia , a 
conspieuons cbromatin-nucleolus occurs, embedded in an acbromatic 
mass in tbe resting cells (figs. 2 and 3). At times, this nucleolus is 
regularly spherical (figs. 2) or dumb-bell iu shape (fig. 3) with a distinct 
clet't or split dividing it into two portions. In otber cells, tbe body 
is irregulär and tbe moieties are unequal. Its origin and fate bave 
not been determined. 
b) Tbe cbromosomes of tbe female. The difficulty of counting 
the cbromosomes in tbe metaphase plate is increased in tbe female 
cells by the "V” shape assumed by tbe chromosomes (fig. 5). Ouly 
three cells have been found wliich permit counts witb any degree of 
accuracy. Tbe clearest of these is represented in figure 5. Here, 
again, alterations of the focus serve to separate tbe cbromosomes 
wliich apparently lie so closely together tbat tliey are not to be 
distinguished. Some of tbe cbromosomes are turned vertically, so tbat 
tliey resemble rods and not "V’s”. 
Thirty four chromosomes occur iu eacli of tbe cells mentioned. 
One of these cells is an oügoniuin, but tbe rest are ovarian follicle 
cells. Tbe writer feels that tbe clearness of tbe three cases suffi- 
ciently otfsets tbe meagerness in number, so tbat be may safely say 
that there is one chromosome fewer in tbe spermatogonia tban in 
the oögonia and follicle cells of tbe ovary. 
c) Tbe odd chromosome. The presence of an odd chromosome 
in tbe spermatogonia is assumed by the difference in the number of 
cbromosomes in tbe male and female cells. Tbe similarity in size 
and shape among the cbromosomes precludes, however, tbe possibility 
of identifying tbe chromosome individually. Moreover, in the resting 
cells between tbe earlier and later stages of tbe spermatogonia, tbe 
odd chromosome is not in evidence. There is no reason to believe 
