236 THE UNIVERSITY SCIENCE BULLETIN. 



which lives in the rivers of Canara and which he says eats fish 

 eggs, from which fact Westwood derived its name. The ob- 

 servation follows: 



"I observed it myself in a still hollow in a rock, where the water was 

 quite clear and only two or three inches deep. The insects kept tossing 

 the ova up from the bottom and following them closely up to the surface 

 whence they gradually subsided to the bottom of their own weight, the 

 insects apparently adhering to eggs all the time, but the moment they 

 were at the bottom they vigorously were tossed up again. I daresay it 

 attacks other spawn also, but the ova I saw it engaged with were those 

 of the Masheer barbas mosal, commonly called 'Masheer,' the most valu- 

 able fish in the Indian rivers." 



Mr. Thomas sent an extract from the report of Pisciculture 

 in S. Canara "detailing experiments made by an intelligent ob- 

 server to test the destructive habits of this insect. In one 

 instance a hollow was watched in which were many freshly 

 deposited ova but no Corixse. The next morning the latter 

 were there in large numbers, and nothing left but the empty 

 egg shells. In another experiment the ova were placed in a 

 finely woven basket and the Corixse immediately came in 

 quantities and endeavored to penetrate from the outside." 



White, 1873, made careful studies of the behavior of Cor- 

 ixids, and described their feeding movements but stated, 



"I have not been able to make out satisfactorily of what the food of 

 these insects consists. (Westwood has recently described an Indian 

 species which is said to feed on eggs of fish.) Evidently White doubts 

 the occurrence of the observation. They often rest on a stone and seem 

 to scrape its surface with the palae which they bring rapidly and alter- 

 nately to the mouth. In the same manner they scrape a root of Lemnae 

 passing it rapidly between the palse. On examining a stone from which 

 a Corixa had apparently been obtaining food, a small alga and a few 

 Rctifera and other animalcules were seen." 



Kirkaldy, 1905, came, through his observations of their be- 

 havior, to state, "Dufour says they are carnasial. I think that 

 small worms, Rotifera, etc., form a large part of their food. 

 Kulgatz, 1911, in "Die aqatilen Rhynchoten Westpreussens" 

 describes the front legs of Corixa as "Organe zum Packen und 

 Frestholten der auszusaugenden Beute" and Brocher, 1913, 

 says fore legs ^re for prehension "Si un petit animal, larve ou 

 elles I'attrapent et le maintiennent applique contre leur 

 bouche . . ." 



The writer has given at some length the observations of 

 others. He has observed Corixids catch prey, but finds that 



