[9] COLLECTING DRAGON AND MAY FLIES NEEDHAM. 



Wliile all but the largest species are easily taken with a net, one may 

 greatly economize time in gathering duplicates by " sweeping" the veg- 

 etation of the shores at sundown. Most desirable stone flies may be 

 swept from the grasses and sedges overhanging small and rapid 

 streams. One should, of course, take advantage of the " swarming" of 

 may flies. The smallest of the stone flies are best picked up with a brush 

 wet with alcohol and put directly into vials of the same preservative. 



It may be worth while to suggest that subimagoes as well as imagoes 

 of may flies should be collected, and that one should try to get both 

 young and old imagoes of dragon flies of the family AgrionidWj of these 

 latter many species have been described as dimorphic, so striking are 

 the differences of appearance at different ages. Males and females 

 taken in pairs should be kept together for the certain identification of 

 the females — often a difficult matter, otherwise. 



Lepidoptera should be rigidly excluded from the cyanide bottles used 

 for killing these insects, for the shed scales are an intolerable and alto- 

 gether unnecessary nuisance. 



PEESEEVATION OF SPECIMENS. 



ISTymphs are best j)reserved in alcohol (about 80 per cent). The more 

 strongly chitinized and impervious ones should be dropped first for a 

 few minutes into water almost boiling; the thin-skinned nymphs of 

 most stone flies and of may flies should be put directly into the alcohol. 

 Imagoes also may be preserved in alcohol, and better, so far as preser- 

 vation is concerned, than by any other method. If kept in the dark 

 the colors will be well retained. Even if one be pinning specimens it 

 is well to have a " stock bottle " of alcohol at hand to catch the large 

 series of duplicates which would never be pinned; for the collector well 

 knows that pinning is a time-consuming process. 



Pinned specimens of dragon flies, at least, should have the body 

 " wired," otherwise heads and tails are certain to fall off and be broken 

 or lost. For this purpose it is well to use beheaded, japanned pins, 

 cut to the proper length ; one is inserted through the front of the head, 

 pushed through the body lengthwise but not protruding; the body 

 dries fast to it and is then not easily broken. If one be not long enough 

 two may be used, one inserted from each end. Formerly a wire or 

 bristle was used, but the pins being well pointed enter easily and effect 

 a great saving of time and temper. Even if specimens are to be put 

 away in envelopes it is better that they should be wired and pinned first, 

 because specimens once dried do not thereafter stick well to the pins. 



The foregoing simple methods and appliances have been abundantly 

 tested in practical work. It is believed they will be found more effective 

 and practical than others generally recommended hitherto. They are 

 offfered in the hope that these interesting orders of so much scientific 

 importance may receive a little more attention at the hands of general 

 collectors, and that materials needed for their study may be more 

 rapidly brought together. 



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