THE CANADIAN ENTOMOLOGIST. 60 



No nymphs of these 

 genera known. 



NYMPHS OF NORTHERN ODONATA, STILL UNKNOWN. 



BY JAMES G. NEEDHAM, LAKE FOREST, ILL. 



This is a word in season to collectors of aquatic insects, who may 

 be afield during the months of spring and early summer. 



Among the nymphs ofOdonata occurring in the North-eastern States 

 and Canada, there remain a number of good discoveries to be made. In 

 any locality where these nymphs are common their discovery will not be 

 a difficult matter. Nymphs of the following half-dozen species are pre- 

 eminently desirable : 



1. Tachopteryx Thoreyi, Sel. Atlantic States. No nymphs of its sub- 



family known. 



2. Gomp/iceschna furciliaia, Say. Eastern States. 



3. Nannothemis bella, Uhl. Atlantic Seaboard. 



4. Neurocordulia obsoleta. Say. Eastern States. 



5. ? Neiirocordulia U/iie?-i, Sel. Me. Mass., N. J. 



6. Somatochlora Lintneri, Hag. N. Y., Saskatchewan. 



The last-named genus, which is peculiarly a northern one in our 

 fauna, is large and polymorphic. Even the imagoes are very insufticiently 

 known, and few nymphs of fewer species have been taken, though they 

 must be very common m proper localities. Canadian collectors have 

 every advantage in the study of this genus. 



While a large number of nymphs of Odonata have been collected 

 and reared of late, descriptions of them have not, unfortunately, as yet 

 got into print. The species above mentioned are among the most 

 desirable of those which have not, I believe, as yet been found. I have 

 had no difficulty in rearing all the genera and almost all the species 

 occurring in the localities in which I have lived during the last five 

 years : but these six have not come my vvay. I should be glad to help 

 any one who wishes to undertake to find and rear these nymphs, by 

 sending a printed account of the methods I have used successfully, and 

 by the determination of dragon-fly material in all stages of development. 



