AQUATIC INSECTS IN THE ADIRONDACKS 



497 



Helocordulia uhleri Selys 



1871 Cordulia uhleri Selys, Acad. Belg. (2) Bui. 21:274 



1890 Neurocordulia uhleri Beutenraiiller, Dragon flies vs mosquitos, 



p. 164 (listed from New Yort) 

 1895 Neurocordulia uhleri Calvert, N. Y. ent. soc. Jour. 3:46 (listed 



from New York) 



This species was not uncommon in Little Clear creek on the hatchery- 

 grounds. Imagos were seen flying a few times about the banks of Little 

 Clear pond close in shore and low above the water. They are so swift 

 and agile, and their wings are so transparent that the eye follows them 

 with difficulty. They are not very difficult to capture however, if one 

 will place himself beside a regular " beat ", and bring his net up behind 

 the dragon fly with a quick stroke when it is passing. I found the ima- 

 gos showing no disposition to avoid me even after escaping a stroke of 

 the net several times. Twice I saw three males chasing one another up 

 and down Little Clear creek, and had httle difficulty in capturing them. 



The nymph was not reared. Some of them, apparently about grown, 

 were kept through the season without result. Apparently, the season for 

 their transformation was over before any were found. There can be 



Fig. 22 Parte of nymph of Helocordulia uhleri Selys. a dorsal view of the head ; b labium, 

 from within, details In part omitted on the right ; c a single tooth from the front border of the 

 lateral lobe of the labium ; d dorsal view of the abdomen ; e lateral view of apex of abdomen, to 

 show better the dorsal hoolcs 



scarcely a doubt, however, as to the correctness of the reference of them 

 to this species, when one considers that the only other corduline observed 

 here like this one in size was D . libera, which I reared. 



The nymphs live in the borders of the creek, mainly in the shallow 

 places, filled with red-rotten vegetable debris — the haunts of the giant 



