Woodburn. — Spermatogenesis in Blasia pusilla , L. 97 
Figs. 6 and 9. No wall has been observed between the spermatids as 
figured by Wilson for Pellia and Allen for Polytrichnm , but the cytoplasm 
separates into equal masses, each of which with its respective nucleus 
becomes surrounded by a plasma membrane. No definite centrosome-like 
body or blepharoplast could be found in those stages represented by Figs. 6, 
7, and 8. About this time, however, a small area of cytoplasm denser than 
the rest appears in one end of each spermatid. The nuclei have in the 
meantime moved somewhat in opposite directions, leaving the cytoplasm 
massed on one side of each nucleus, or in opposite ends respectively of each 
of the pairs of spermatids (cf. Fig. 6 , 7, and 8). Fig. 8 represents one of 
a pair of spermatids drawn from the same section as Fig. 6, but viewed 
from the back or flattened side, if we speak of the view in Fig. 6 as from 
the edge. The evidence obtained from a careful examination of the stages 
similar to Figs. 5, 7, and 9, leaves little doubt that the blepharoplast arises 
as a differentiation of cytoplasmic material, and agrees with facts observed 
and described for Porella and Fegatella. A little later, in each spermatid 
in the region where the dense area of cytoplasm appeared (Fig. 6) there is 
found a definite granule or body (Fig. 9). The different writers are quite 
agreed upon the appearance of this body in the early stages of the spermatid, 
but not upon its origin and nature. While Wilson does not trace it through 
the various stages of the last division, yet he thinks it probably arises from 
a centrosome-like body. 
Allen concludes that this is the same morphological entity as the 
* central body 1 which often appears so prominent during the earlier phases 
of karyokinesis in the * androcyte ’ mother-cell. 
The results of the writer’s observations in regard to the persistence of 
this body throughout the various phases of the last division of the spermo- 
genous tissue in the Hepaticae have so far been only negative. 
The granule, or blepharoplast, as we may call it, since the latter term 
indicates its function, grows gradually into a cord along or near the peri- 
phery of the cell (Figs. 9, 10, and 11). Fig. 11 shows with remarkable 
clearness the course and appearance of the blepharoplasts in each pair of 
spermatids. The one on the right shows the blepharoplast as a cord passing 
from end to end of the spermatid over the nucleus next to the observer, 
while the one to the left shows merely the two ends of the cord as the 
middle portion is hid behind the nucleus and cytoplasm. There is good 
evidence here that the blepharoplast is formed within the plasma membrane 
embedded in cytoplasm, and is not a differentiation of the former. The 
blepharoplast, moreover, appears as a homogeneous cord throughout. The 
author has taken especial pains to observe its development from its 
beginning as a small round body until a considerable length has been 
reached (as in Fig. 11), and no secondary cord has been observed joining 
the blepharoplast to the nucleus, as one or two writers have recently 
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