1912] GRIGGS—RHODOCH YTRIUM 161 
by any abnormality the amount of chromatin is increased, as when 
a nucleus passes through the prophases of mitosis but fails to 
divide, the karyolymph is proportionately increased. The char- 
acteristic phases of the nucleus, vegetative and mitotic, are marked 
off from each other principally by the appearance and dispersal of 
the karyolymph. Indeed, it is a general rule that whenever the 
karyolymph is absent, the anabolic activity of the cell is suspended. 
The characteristic condensed condition of sperm nuclei is another 
illustration. The shriveling of the nuclei of the resting spores in 
Rhodochytrium above described is due to the partial disappearance 
of karyolymph when grcwth ceases and the dormant period is 
entered upon. 
SEGMENTATION.—In regard to the process of segmentation, the 
uncertainties encountered in Rhodochytrium are largely duplicated 
in Synchytrium. HARPER (12) reported that segmentation occurs 
by the formation of cleavage furrows, which begin to penetrate the 
cytoplasm at a relatively early stage in the multiplication of the 
nuclei. Kusano (18) found that while some cysts undergo pro- 
gressive cleavage, as described by HARPER, others show simultane- 
ous segmentation by the precipitation of membranes around the 
segments. My own observations, like Kusano’s, showed both of 
these methods of segmentation, but in my material the progressive 
cleavage described by HARPER was infrequent. The apparent 
duplication of segmentation recalls the double contraction reported 
in various phycomycetes and certain algae, such as Hydrodictyon 
(KLEBS 14, TIMBERLAKE 30). But it is not easy to correlate the 
accounts of observations on living and on fixed material, and 
for that reason the writer finds himself unable to interpret the 
phenomena satisfactorily. 
Alga or fungus? 
Having examined the morphology and cytology of the plant, 
we may proceed to consider its relationships. Since it is an obligate 
parasite without chlorophyll, one naturally wonders how it was ever 
referred to the protococcoid algae. On a superficial examination 
certainly, it would appear that the plant is no alga but a chy- 
trideaceous fungus. The first question that arises, therefore, is 
