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NEW YORK STATE MUSEUM 



h .Sqaattinjr nymphs, with the face vertical and the eyes capping the prominent 

 anterohiteral angles. These settle themselves on the trashy pond bottom, 

 some of them covering themselves over completely with sand or silt, and 

 thus await in ambuscade the approach of their prey (Cordulegasterinae, 

 Macromiinae, and some Libellnlinae) 



c Climbing and clinging nymphs, with cleaner, slenderer, more active bodies, 

 generally showing a definite color pattern, with the head neither euueate 

 nor vertical in front (Agrionidae Aeschninae, and some Libellnlinae) 



All nymphs, when ready for adult life, crawl up some support above 

 the edge of the water, nx their claws firmly and transform; the old 



nymph skin is left attached when the 

 imago flies away. Since this skin pre- 

 serves well the form of the nymph, 

 and can be pinned for the cabinet, an 

 easy way to gather life history mate- 

 rial for dragon flies is to pick them up 

 when newly transformed and before 

 the images are ready to fly, place in a 

 coarse paper bag each imago with its 

 cast nymph skin, writing locality, date, 

 etc., on the bag and closing its top, 

 leave a day or more till the imago 

 Fig.7 The transformation of PI a the mis assumes its mature coloration, and 



lydla Dru. 1,2,3, three stages m the emerg- ' 



ence of the imago from the Old nymph Skin ^^^^ preserve as Specimens, being 

 always careful so to label imago and nymph skin that future mixing of 

 specimens will be impossible. 



The two suborders, of which but one is treated in this paper, may be 

 readily recognized by the following characters. 



a Fore and hind wings similar, held vertically in repose: nymphs with three 

 large leaflike respiratory plates at the apex of the slender abdomen, and 

 with the body tapering posteriorly from the head. Suborder ZYGOPTERA : 

 damsel flies 

 aa Fore and hind wings dissimilar, the latter broader at the base: nymphs 

 without external respiratory plates, but with a respiratory chamber in- 

 cluded within the wide abdomen ; body less slender, and not widest across 

 the head. Suborder anisOPTERA ; dragon flies proper 



Suborder ANISOPTERA 



The dragon fly fauna of New York state is somewhat more extensive 

 than that of the few other states in which careful collecting has been 

 done. Dr P. P. Calvert has summarized the local lists of the dragon flies 

 of the state in the Journal of the -New York entomological society,^ giving 



-48andlS97, 5 : 91-98. 



