140 THE CANADIAN ENTOMOLOGIST. 



tion for anatomical and histological purposes. The dead bugs should be 

 put in about 75% alcohol, with some punctures made with a needle at the 

 membranous parts and body-joints in order to allow the preservative fluid 

 to enter the body-cavity, otherwise it will not penetrate and the " innards " 

 will dscay, bloating and distorting the specimens for any purpose. For- 

 maldehyde, while an excellent preservative for tissues, according to my 

 observation, hardens specimens too much and makes them too' brittle. 

 For the cabinet, they should be n^ounted while fresh, and in this way the 

 Waterbugs preserve their natural colours much better. If this be not possi- 

 ble at the moment, they should be allowed to dry partially and put in 

 layers in cotton, between sheets of soft tissue paper. The Velias, how- 

 ever, and in general, the smaller Water-striders should be put in alcohol, 

 which, by keeping them flexible, preserves the antennpe and legs unbroken. 

 The larger bugs should be pinned through the scutellum ; the smaller, 

 including Plea, Buenoa, Hydrometra and the more minute Water-strider, 

 are best mounted on points. Of course, the usual locality and date label 

 should not be omitted, and it is also well to make field notes on habits, or 

 the conditions under which the bugs were found. 



One of the most interesting and profitable features of collecting 

 Waterbugs is the excellent opportunity they offer for observation and 

 study. As water is necessary for their comfortable existence, it is a simple 

 matt^ to confine them in an aquarium and with care to preserve them to 

 a hoary old age. For collecting the living insects, I have found nothing 

 better than a dry tin box and in it enough excelsior, much pulled out and 

 separated, to give the bugs something to cling to and to prevent them 

 from coming together in a mass at one end of it, which is fatal. As they 

 are air-breathers in all stages, water is not necessary in carrying from the 

 field to the aquarium ; on the contrary, it is very harmful, and even exces- 

 sive dampening of the excelsior in the box may have bad conseqijences. 

 The best for the purpose are those soldered and hinged tin boxes in which 

 fifty or one hundred cigarettes are packed. They are of a very convenient 

 size to carry in the side pocket of a coat. Several should be carried when 

 out collecting, in order not to.be obliged to crowd too many bugs into one 

 box. Belostomas should never be put in the same box with other bugs, 

 because, being bigger and^ heavier, they are apt to hurt them. For the 

 little Water-striders nothing is better tlian a small test tube lined with 



