78 SPERMATOGENESIS AND FECUNDATION OF ZAMIA. 
In Marsilia the matter is more doubtful. Belajeff investigated the 
spermatogenesis of Marsilia particularly to determine the relationship 
of the blepharoplast to spindle formation, and he describes it as occur- 
ring at the pole of the spindle, thus fulfilling the requirement of posi- 
tion for a centrosome. Figures are given illustrating numerous 
spindle fibers extending from the nucleus to the blepharoplast, in the 
early stage of spindle formation, before the nuclear membrane has 
disappeared. It must be admitted that if these figures are directly 
translated in the ight of previous knowledge of the centrosome ques- 
tion we can hardly escape the conclusion that the bodies must serve 
the purpose of a genuine centrosome in spindle formation, no matter 
what their later function may be. It seems surprising, however, that 
no radiations extend out from the blepharoplast into the cytoplasm on 
other sides than toward the nucleus when the spindle fibers would 
appear from the figures to be so plainly visible. The centrosome 
usually forms the center of an aster, the rays of which extend out in 
all directions. Yet judging from Belajeff’s figures there is no indica- 
tion of such radiations in J/arsdlia. It would seem possible that in 
Marsilia the blepharoplast may be independent of the spindle, though 
occupying a position near the meeting point of the converging spindle 
fibers. Such a body being present in the cell and normally in close 
proximity to the pole of the spindle, it is not surprising that it might 
appear in some instance to be nearly related to the spindle. Stras- 
burger (112, p. 198) says that the blepharoplast is active kinoplasm, 
and that its collection at the pole of the spindle in spermatogenous 
cells of M/arsilia does not signify particularly as to its relation to the 
spindle threads. 
The writer is well aware that the great majority of investigators 
would consider Belajeff’s figures and investigations as conclusive evi- 
dence of the centrosome nature of the blepharoplast, and the views of 
this brilliant investigator must meet with careful consideration. The 
matter is far from settled, however. In the light of Strasburger’s 
investigations on swarm-spore formation and the origin of the cilia in 
these organs from a blepharoplast, the independent nature of the 
blepharoplast can not be set aside without further light on the spindle 
formation in Marsilia. 
In regard to the occurrence of the blepharoplasts of Zama it may 
be said that they are of very limited duration, occurring only in the 
central cell, where they originate de novo, and enduring through the 
division of this and the formation of the spermatozoids. They occur 
thus in only a single division with which they have no material con- 
nection. After fecundation they are lost and do not appear again until 
the central cells of the next generation are developed in the pollen 
grains. The same is true also of Cycas and Ginkgo. In Marsilia, 
according to Shaw (102), bodies similar to the blepharoplasts, which 
