346 BOTANICAL GAZETTE [NOVEMBER 
of Synchytrium have been named karyodermatoplasts by Kusano 
(13). Although somewhat long, this term may be useful in alluding 
to the junction of the asters, but there seem to be certain objections 
to its use as the name of a structure. First, the structure so desig- 
nated is so variable that it is difficult to define it. Sometimes the 
_ aster is single, sometimes double or triple (fig. 2); sometimes it has 
one clearly defined granule at the focus of the rays; more often there 
are several such granules more or less eccentrically placed; or there 
may be none at all. Sometimes there is an elongated band which 
bears radiations all along its length, like the blepharoplast of a 
cycad. It is evident that the term karyodermatoplast can be defined 
only by its function, while such a term should rest on a morphological 
basis. Second, though the aster, so far as observation has yet indi- 
cated, serves only to reconstruct the nuclear membrane, that function 
alone does not seem to the writer adequate to account for its enormous 
development in Synchytrium. This is more apparent when one recalls 
the fact that in heteroschizis and nuclear gemmation the membranes 
of the daughter nuclei are formed without the intervention of any such 
structure. I have preferred, therefore, in the present discussion to 
employ the descriptive term aster for the structure in question, without 
committing myself to its significance. The question of the radiate 
structures in Synchytrium and their homology is one of very great 
interest and deserves consideration in a separate paper. 
The chromosome number 
Inasmuch as most of the nuclei or their ancestors have been derived | 
by amitosis, as has been previously shown, the determination of the 
number of chromosomes in Synchytrium becomes a matter of much 
more importance than in organisms where the orderly sequence of 
mitosis has not been interrupted. On this account especial care has 
been taken to insure accuracy of observation and interpretation. 
Upward of 500 slides have been used in the study. Altogether several 
hundred mitotic cysts with many thousands of individual spindles 
have been observed. Of these only the most favorable were used for 
basing the conclusions. The location of the cysts containing these 
most favorable spindles was recorded by vernier readings of the 
mechanical stage and filed in a card catalogue, so that they could be 
