1912] GRIGGS—RHODOCH YT RIUM 165 
taken by Linpav (20), who excludes it from the algae on account 
of the absence of chlorophyll. If, on the other hand, the matter is 
to be decided by the relationships of the plant, it is clear that since 
its nearest affinities are with undoubted algae, Rhodochytrium must 
be considered an alga. It is not a matter of great consequence 
whether such an organism is considered a fungus or an alga, so 
long as its real affinities are recognized. But in the case of Rhodo- 
chytrium it will probably be more convenient to consider it with 
the algae than with the fungi, since it can be satisfactorily 
approached only from the algal side. 
Evolutionary inferences 
But although Rhodochytrium is to be considered the extreme of 
an algal series and not a near relative of any of the Archimycetes, 
the phyletic position of the Phyllobiae, taken as a whole, remains 
to be considered. We have here a series of endophytes culminating 
in a colorless parasite. Does this line of evolution end blindly, or 
do these forms furnish the clue to the origin of some fungal group ? 
Nearly forty years ago, before Phyllobium, Rhodochytrium, and 
Endosphaera were discovered, CoHN (6) recognized the general 
similarity of his newly discovered Chlorochytrium to Synchytrium, 
and suggested that the two were phylogenetically connected. 
There are now known far more points of similarity in gross 
morphology between the different genera of the Phyllobiae and 
Synchytrium than those which induced CoHN to make the com- 
parison. Indeed, could one construct a plant with a combination 
of characters from the different genera, he would have a very 
satisfactory transition to Synchytrium. Such a hypothetical plant 
would be an obligate parasite definitely limited to specific hosts, 
like Rhodochytrium. But it would have no rhizoids, retaining © 
rather the simple spheroidal form of Chlorochytrium and Endo- 
sphaera. It would have simultaneous segmentation like Rhodochy- 
trium, but. the segments would become sporangia rather than 
zoospores, as in Endosphaera, which has substantially the same 
method of reproduction as Synchytrium, except that the swarmers 
conjugate, while in Synchytrium no sexual process is known. It 
would have lost its plastids, and instead of having chlorophyll 
