8 ENTOMOLOGICAL NEWS [Jan., '15 



algae were found frequently, but were supposedly taken in by 

 accident. The eggs recorded were thought to be those of a 

 dragonfly. 



The large majority of animals eaten were insects, the total 

 number being 95. Five orders were represented, the numbers 

 in each being Ephemerida 8, Hemiptera u, Diptera 62, Cole- 

 optera i, Odonata 13. The closely allied groups of Crustacea 

 (13) and Hydrachnida (4) with one snail in addition com- 

 pleted the list. (See page 9.) 



EPHEMERIDA. Four Heptagenias were eaten by four 

 nymphs, Basiaeschna, Syinpetrum, Plathcmis and Calopteryx, 

 representing three families of quite different habits. Hexa- 

 genia was eaten by Anax jnuius, Cacnis by Plathcmis, and 

 two mayflies eaten by Basiaeschna and Calopteryx were not 

 well enough preserved to be identified. 



HEMIPTERA. This group is represented by the nymph of 

 the waterbug Corisa, found the last of April, three of which 

 were eaten by Lencorhinia Intacta, and one each by Plathcmis, 

 Basiaesclina and Calopteryx, again showing a similar diet in 

 three different families. Two adult w 7 aterboatmen were eaten, 

 one each by Sympetrum and Gomphus sordidus respectively 

 in March. 



DIPTERA. The number of Chironomid larvae far exceeded 

 that of any other animal or group. They constitute the "staff 

 of life" for the nymphs because they are at all seasons abun- 

 dant and available.* They were eaten by all of the species 

 examined except Pachydiplax, which was probably an acci- 

 dental omission. Sympetrum, taken on November 30 with a 

 mayfly and a damsel fly besides 22 Chironomids, most of which 

 were in almost perfect condition, is an example of the appetite 

 and capacity of one of the smaller nymphs. Size seems to 

 have made little difference in the choice of food. 



The following species of Chironomids were identified in the 

 food : I Chironomus tenellus Zetterstedt, i Ch. f lavas Johann- 

 sen, i Ch. modestus Say, 4 Tanytarsus dissmiilis Johannsen, 



*This is especially true in the Winter, when mayflies and the young 

 of their own kind seem to be the only alternatives. 



