Observations on Saprolegnie(B. 145 



dition of Empusa mjiscce, Cohn., as the specimens were grown 

 in the fall and winter. I have made some experiments bear- 

 ing upon this point, the results of which I am not prepared to 

 give in detail now, but as a whole they tend to disprove it. 



I have never seen any mention made of American forms of 

 this group, but as far as my observations have gone, I find as 

 great a difficulty in identifying them with European species 

 as in the case of the higher Fungi; the variation being in 

 many cases truly specific differences. The group, as a whole, 

 makes a very interesting microscopical study, and those 

 doing microscopical work will find it well worth the while to 

 give specimens with which they may meet, at least a passing 

 observation. They flourish in springs, water-tanks, and 

 fresh pools, also in aquaria containing water-plants. In the 

 vicinity of Cornell University, I have recently found eight 

 different species, representing the genera Leptomitus, Agardh; 

 Saproiegnia, Eseub.; Pyfhrum, Pring. ; Dictyi/chus, Leitgeb.; AcJilya 

 and Monoblepharis^ Cornu. 



When valuable specimens in aquaria are attacked by these 

 parasitic plants, the following may prove of some use. Mr. S. 

 H. Gage, of the anatomical laboratory of Cornell University, 

 informs me that he effectually removed a species of Sapi-oleg- 

 nia which had become well seated on an eel, by sponging the 

 animal with a ten per ce?it. solution of carbolic acid; also that 

 specimens of Menobranchus infested by the form of Saproleg- 

 nia treated of in this paper, were thoroughly cleansed by 

 carefully sponging them with camphorated water. Rev. M. J. 

 Berkeley in the "Treasury of Botany," states: "it is said that 

 doses of carbonate of soda prevent their growth, and if so it 

 is probable that bisulphate of potash may be more effectual 

 from its known effects on obscure cryptogamic growths." 



In closing I wish to acknowledge the kindness and encour- 

 agement of Professor A. N. Prentiss, through which the pro- 

 duction of this paper has been rendered possible. 



WORKS AND PAPERS REFERRED TO. 



1. Berkeley, M. J.; Introduction to Cryptogamic Botany. 



2. CoRNU, M.; Monographic des Saprolegniees, etude physio- 

 logique et systematique (Ann. des Sc. Nat., tome VI., Bot., 1872). 



3. Hildebrand; Notes Mycologiques, translated from Pring- 

 sheim's Yahrblicher (Ann. des Sc. Nat. Bot., t. VIII., 1867). 



Fig. 4. LiNDSTEDT; Synopsis der Saprolegnieen, Berlin, 1872. 



