172 
Charles E. Allen 
of Dioon may be formecl from material which he thinks is of nuelear origin. 
The blepharoplasts of Gingko (Hirase, 1898), Zamia (Webber, 1897 a , 
1901), and Cycas (Ikeno, 1898) oceupy positions in the spindle axis during 
the division of the androcyte mother nucleus, but are not at the poles. 
One figure given by Caldwell suggests that in Microcycas the blepharo- 
plasts do occupy the spindle poles. 
While some of these diserepancies of opinion concerning the origin and 
history of the blepharoplast are doubtless based upon actiial differences 
between members of different Orders of plants, much of the pre valent 
eonfusion evidentlv results from partial and inaccurate Observation; and 
it is not unlikely that future careful study will reveal a greater degree 
of uniformity than is now apparent. With reference partieularly to the 
bryophytes, it is to be noted that all the studies of blepharoplasts 
hitherto published are incomplete, and in most cases extremely frag- 
mentary; and even some of the more pretentious present figures so 
unconvincing that little reliance can be placed upon their statements 
regarding disputed points. Nevertheless , I think it is reasonable to 
antieipate, even upon the basis of the evidence now available, that 
future study will show a substantial agreement on the part of other bryo- 
phytes with the history of the blepharoplasts in Polytrichum\ at least, 
upon such fundamental points as their formation by the division of a single 
body, whieh, aceompanied by an aster, first appears in the eytoplasm of 
the androcyte mother cell; the migration of the daughter blepharoplasts 
to the poles of the future spindle; their centrosome-like behavior in the 
ensuing division; and their ultimate distribution to the respective daughter 
cells. 
A similar prophecy can hardly be ventured with reference to the 
blepharoplasts of other groups of plants, however much one may be in- 
clined to look for uniformity of behavior arnong bodies which are so similar 
in many respects. We should not be justified, for example, in maintain- 
ing that the blepharoplasts of the characeae originate in the androcyte 
mother cells, when no observation is reeorded of the occurrence of such 
bodies in these cells: or that the two blepharoplasts which appear in each 
androcyte mother cell of the pteridophytes and the more primitive sper- 
matophytes must originate from the division of a single body, in view of 
the present preponderance of evidence to the contrary. It is true that in 
these respects the apparent diversity is based upon negative evidence; 
but whcther or not this diversity is onlv apparent must be left for the 
present undetermined. 
