4 8 
The Ohio Naturalist. 
[Vol. X, No. 3, 
general appearance is identical with that of the resting spores of 
Synchytrium which Von Gutenberg has recently determined to 
be chitinous. On account of the scarcity of material, however, 
michrochemical tests to determine its composition were not 
undertaken. 
General Considerations. 
The relationships of Monochytrium are in the present state of 
our knowledge regarding the Chytrids somewhat obscure. Its 
method of parasitism and general structure are similar to those 
of Synchytrium and, had the present plant been described with- 
out reference to its cytology, the only difference between the two 
genera that would have been noticed is the difference in seg- 
mentation which in Synchyrium results in the formation of 
zoosporangia each of which in turn gives rise to numerous 
zoospores while in Monochytrium the zoospores are formed 
directly, each cyst becoming a single zoosporangium. This 
difference is however of itself sufficient to remove the plant from 
the Synchytriaceae and place it among the Olpidiaceae. From 
all the genera of this family Monochytrium may be separated at 
once by its habitat. All the other genera are parasites of 
aquatic plants or animals except Asterocystis which infests the 
roots of the seed plants. 
So far as the writer is aware in no other plant has a conjuga- 
tion of gametes been reported to occur after the young parasites 
have infected their host. But when the cytology of the lower 
organisms especially of their early stages is better known it may 
be found that such a conjugation is not so rare as now appears. 
It is quite possible that man}^ forms now supposed to be non- 
sexual may conjugate after infecting their host. The life history 
of most species of Synchytrium for example would seem to 
demand some difference in constitution between the summer 
sori and the resting spores similar to this belated conjugation of 
Monochytrium; but if such a sexual act exists it is obvious that 
in these cases the nuclei also must fuse. The continued inde- 
pendence of the nuclei of the zvgote may be more unusual but 
when it is recalled in how few of the zvgospores of the lower 
plants are the actual conditions of the nuclei known, it is evident 
that such a plasma conjugation may be more common than now 
suspected. This long continuance of the apylogamic phase in 
Monochytrium cannot fail to recall the similar phenomena in the 
nuclei of the higher fungi. Nothing could be of greater interest 
than to determine the fate of these two nuclei in the germination 
of the resting spore. Attempts at germination must however 
wait upon more abundant material than is now available. 
It is hoped that an opportunity may also be presented to 
observe the zoospores in the living condition in order to deter- 
