No. 460.] STUDIES ON PLANT CELL.— V. 239 
esting account accompanied by clear figures gives an explanation 
far more in keeping with what we know and might expect of the 
behavior of chromatophores in resting spores. That the green 
chromatophore may temporarily become much modified in color 
and form is well known in some of the red and orange resting 
spores of the Volvocacez and the zygospores of the desmids. 
In some of these types the form and color of the chromatophores 
become quite lost for the time being so that studies on their 
behavior are very difficult. For these reasons it seems probable 
that the accounts of the fusion of the chromatophore in the zygo- 
spore of Spirogyra are incorrect. It is very interesting that the 
gametes of Spirogyra should be so sharply differentiated that the 
chromatophore of one should be reduced during conjugation in 
a manner that resembles very closely the behavior of the chro- 
matophore in highly differentiated sperms. 
There is no evidence that the pigment spots, so generally 
present in the motile gametes of lower forms, ever unite. They 
have been followed into the zygospore and after the germination 
of this cell and they remain entirely independent of one another 
as would be expected from their close relationships to chromato- 
phores. 
The fate of the blepharoplast will now be considered. This 
structure is especially interesting because of its close analogy to 
the locomotor apparatus of the animal spermatozoön, which is 
formed chiefly from one or more centrosomes generally with the 
coóperation of archoplasm (idiosome, Nebenkern). It is also 
claimed by a number of zoólogists that in some forms, at least, 
the centrosomes of the first cleavage spindle are derived from 
the spermatozoón. 
All evidence indicates that the blepharoplast of the plant 
sperm is left behind in the cytoplasm of the egg when the male 
nucleus passes into the interior to unite with the female and 
that centrospheres when present, in the first cleavage spindle, 
are formed de novo. The fate of the blepharoplast is clearly 
known in Cycas (Ikeno, '98b), Zamia (Webber, : 01) and Ginkgo 
(Ikeno, :or). Soon after the large top-shaped sperm of these 
forms enters the egg, the male nucleus slips out of the spiral 
blepharoplast, that partially invests it, and, leaving it with 
