AQUATIC INSECTS IN THE ADIRONDACKS 397 



been able to give in part 3 an account of the dragon flies (suborder 

 Anisoptera of Odonata) which is almost a monograph of the New York 

 species of tliat group. 



But two species of stone flies were seen at Saranac Inn. Both of these 

 were reared, and the descriptions of their nymphs, published herewith^ 

 appear to be the first to be printed for American species. 



I have been able to rear representatives of all the New York genera of 

 May flies,, and present in part 3 a key for the determination of the nymphs 

 of the same — apparently the first key to be published for American 

 forms. 



In the Neuroptera, with its two families having aquatic genera, I have 

 been able to straighten out a tangle in the Sialidae, and to report the dis- 

 covery of larvae and pupae of two genera of Hemerobiidae. These two 

 are both new species of spongilla flies, representing two genera whose 

 larvae live on fresh-water sponges. Entomologically, their discovery was 

 one of the best things of the season. Our account of the aquatic Neu- 

 roptera is thus considerably more complete than any that have hitherto 

 appeared. 



Mr Betten occupied himself during the intervals of routine operations 

 with the study of the habits and transformations of the caddis flies. He 

 has written the account of this order in part 3. He collected many speci- 

 mens in all stages, and reared four species representing as many genera. 

 His descriptions seem to be the first that have appeared for American 

 larvae. It is a matter of regret that specific determinations could not 

 be had for more of the material in this little studied group. He has pre- 

 pared a table for caddis fly larvae, compiled from the descriptions of 

 European writers and verified, so far as possible, on his own material, 

 and while it is tentative and incomplete, it will doubtless serve a 

 temporary purpose. 



Aquatic larvae of flies and beetles were abundant at Saranac Inn, but 

 there was little time available for their study after attending to the others 

 mentioned above. A few of the more interesting ones were reared, how- 

 ever, and will be found described in part 3. The three bred Diptera 

 there described make an interesting addition to our knowledge of the 

 larvae of that order. 



Apparatus and methods. Litde need be said on this head. We 

 used the insect nets, cyanid bottles, setting boards, pins, and preserva- 

 tives used by all collectors; but our main stay in aquatic collecting was 

 the sieve net^ which is shown in use in plate 4; leaning against a tree in 



1 Described and figured In part O of U. S. nat. mus. Bui. 39, p. 4. 



