l88 NEW YORK STATE MUSEUM 



averaging perhaps two thirds grown) were thrown into the 

 tank twice daily in sufficient numbers so that each day a few 

 remained over, uneaten. They were simply thrown on the 

 bottom where they were snapped up promptly so long as tlie 

 fish were hungry. The number disposed of during the preceding 

 interval was recorded at each feeding. The average number 

 eaten by the half grown Chrosomus was ii per day, by the full 

 grown ones, 25 larvae per day. The largest number was dis- 

 posed of at the first feeding, but the figures were maintained 

 fairly uniform after the third day ; evidently these larvae are 

 choice food for Chrosomus. The experiment was abandoned 

 after 22 days because of the great difficulty found in supplying 

 sufficient Chironomus larvae. 



That the adult midges are quite as attractive food for Chroso- 

 mus as are the larvae is indicated by the following field observa- 

 tions made by Mr Ferguson: 



It is very interesting to watch the fish feeding. The midges 

 hovering over the water seem to attract them most. Usually the 

 minnows are satisfied to wait till the midges touch the surface of 

 the water, but quite often they spring several inches out of the 

 waler to catch them. 



NEW DATA CONCERNING MAY FLIES AND DRAGON FLIES 



OF NEW YORK 



May flies 



(Ephemeridae) 

 Under this heading will be included a brief account of the May 

 fly fauna of Old Forge, and descriptions of a few new forms col- 

 lected by Dr C. Betten at Buffalo and vicinity in the summer of 

 1906. At Old Forge, May flies were abundant, and no place in 

 which I have ever collected better exemplifies the need of different 

 methods, and of collecting from different types of situation, and 

 at different hours of the day, if one would really know the INIay 

 fly fauna. There was a very familiar group of species (Siphlurus, 

 Epheremella, Heptagenia etc.) that settled upon the outside of the 

 hatchery and that could be found anywhere about the banks of 

 Old Forge pond where shelter and good resting places offered. 

 Then there were some others (Caenis, Chloeon) that were only to 

 be found at night at the time of their emergence from the water. 

 A few, like Leptophlcbia, Chloroterpes and Bactis could be found 

 on still afternoons swarming in great companies in the hollows of 

 the wood, especially over little pools or in their vicinity, and there 



