Collecting and Preserving Insects 



Professor Comstock has invented and described a root-cage 

 in order to study underground insects. This is a metal cage 

 with glass sides, made narrow, and with galvanized iron additional 

 sides which can be slipped down over the glass ones so as to 

 keep the cage dark when not under observation. Plants and 

 insects are placed in earth between the two glass sides, and the 

 whole apparatus is then placed in the ground. It can be pulled 

 up and the insects watched through the glass. 



For insects feeding upon grasses it is well to make a wooden 

 box two feet deep with bottom perforated with a few 

 auger holes covered with wire netting and containing a good 

 supply of growing grass. The box should be of good size, say 

 2x2x2 feet. Little upright posts or sticks or laths six inches 

 high should be nailed to the corners of the box, and gauze mos- 

 quito netting or something finer tacked over the whole. This 

 kind of a box is of good service in rearing grasshoppers, which 

 are the most difficult insects to rear. Confined in a small 

 breeding cage they feed little, and are apt to fatally exhaust 

 themselves in futile efforts to escape. Boxes for these insects 

 should be about three feet square, and in the earth should be 

 growing not only grasses but also weeds of various kinds. The 

 long-horned grasshoppers (Locustidse) are very easy to rear in 

 confinement, and need only be given an occasional supply of 

 fresh food. This is the case also with the walking-sticks, and 

 mantids, the latter requiring no moisture whatever beyond that 

 which they get from the bodies of their victims. 



That reminds me that one of the difficulties encountered in 

 the rearing of insects is the proper maintenance of the right de- 

 gree of moisture. Galls of all kinds are aot to be left either too 

 dry, in which case the issuing of the insect is delayed far beyond 

 the normal time, or too moist, in which case they become covered 

 with mildew and spoil. If the jar containing them be left open 

 they dry no matter how frequently sprinkled. If it be closed 

 mildew frequently puts in its appearance. This difficulty is ob- 

 viated by keeping them in a series of jars of the same height, the 

 mouths of the jars being covered with gauze to prevent the 

 escape of the insects or parasites. Over the whole series is laid a 

 large sheet of blotting paper which is moistened daily and the 

 insects seem to thrive under this treatment. In rearing Hymen- 

 opterous parasites, the breeding jar should be tightly closed and 



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