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easily secured by capturing the ovipositing female and touch- 

 ing her abdomen repeatedly to some water in a small dish, 

 holding her only by the fore wings back to back, while those 

 which oviposit in plants or soft wood may be watched and the 

 stems or wood examined afterward. Experiments indicate that 

 imagos will not voluntarily oviposit while in captivity. 



Formalin is not a good preservative for any of the larger 

 insects. The best preservative is strong alcohol carefully 

 heated in a water-bath. The hot alcohol penetrates more rap- 

 idly than cold, arresting internal decomposition, and thus re- 

 tains the beautiful but fugitive colors of the imago. The usual 

 process of sterilizing and fixing the tissues by heating in water 

 in a test-tube to the boiling point before transferring to alcohol 

 is eminently satisfactory for aquatic forms as a rule, but in the 

 Anisoptera this expands the air in the rectal gill-chamber and 

 distorts the abdomen somewhat, while in the Agr ion idee, as in 

 the Ephenieridw, the flat external gill-plates are badly injured 

 by inflation and gumming together. The slender and brittle 

 abdomen of the imago breaks off very easily, and a bristle or 

 fine non-corrosive wire should therefore be passed lengthwise 

 through the body as far as the tip of the abdomen, but not so far 

 as to project among the terminal appendages. A couple of insect 

 pins, inserted lengthwise, one at each end of the body, are 

 used by some. Specimens for the cabinet may be spread like 

 Lepidoptera. For shipment or exchange they are usually in- 

 closed in soft papers folded diagonally. 



Rearing the nymphs is not usually diflicult. They need 

 plenty of clean water, something to crawl out on, and room to 

 transform in. A pail or tub covered with mosquito-netting 

 answers nicely. It must get plenty of sunshine, but not so much 

 as to overheat the water. If the breeding-cage can be immersed 

 in the water of the stream or lake where the nymphs live, suc- 

 cess is almost assured. They may be fed bits of fresh meat or 

 fish, insect larvae, flies, or the smaller aquatic Hemiptera. If 

 meat is fed, it must be kept in motion before them, as they will 

 refuse anything that does not seem to be alive. Mr. Needham 



