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VOLUME XLVIII NUMBER 5 
BOTANICAL GAZETTE 
NOVEMBER 1909 
SOME FUNGUS PARASITES OF ALGAE" 
GEORGE F. ATKINSON 
(WITH EIGHT FIGURES) 
About twelve years ago I was giving considerable attention to the 
study of the parasites of the algae in the vicinity of Ithaca, N. Y. 
At that time I hoped that the investigations might eventuate in a 
Monograph of the Chytridiales of the Cayuga Lake basin. The 
Pressure of other investigations has almost completely interrupted 
these studies. Because of our limited knowledge of the occurrence 
and habits of these interesting fungi in North America, it has seemed 
to me desirable that the observations already made should be recorded, 
In the hope that this may stimulate a greater interest in these plants. 
As a result of the studies three papers have already been published. 
An extended paper on the genus Harpochytrium in the United States 
Was published in 1903,? a summary of which later appeared in the 
Journal of mycology in 1904.3 A short note on the interesting behavior 
of the zoospores of Rhizophidium globosum while escaping from the 
Zoosporangium was published in 1894.4 This behavior related to the 
habit of their sensing or feeling the exit opening in the sporangium, 
which they do by means of pseudopod-like extensions of the proto- 
Plasm in different directions, after having come to rest on the inside 
of the zoosporangial wall. In case they happen to come to rest close 
by the exit they “feel” it by one of the pseudopods, and slide out. 
‘ Contribution from the Department of Botany, Cornell University, No. 133. 
* ATKINSON, G. F., The genus Harpochytrium in the United States. Ann. Myc. 
1:479-so2. pl. Io. 1903. 
*-———., Note on the genus Harpochytrium. Jour. Myc. 10:3-8- pl. 72. 1904- 
é +++, Intelligence manifested by the swarm-spores of Rhizophidium globosum. 
OT. Gazetre 192503, 504. 1894. 
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