METHODS OF COLLECTING INSECTS 



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667 



Another form of chloroform bottle suitable for stupefying large 

 Lepidoptera is made by inserting a fine-pointed medicine dropper 

 through the cork of the bottle. A few drops of chloroform can then 

 be applied directly to the specimens, through the net, before they 

 are removed. This will also be found convenient in collecting some 

 of the larger Hymenoptera. Since the chloroform has a tendency 

 to harden the specimens, only a sufficient amount should be used 

 to stupefy the insects, which should immediately be placed in the 

 cyanide bottle. 



Alcohol. This is another accessory that should be used in the 

 field only in collecting very small insects, such as Thysanura, very 

 small larvae, Aphididae, etc. The alcohol outfit should consist of 

 a number of small, straight-necked vials, fitted with cork stoppers, 

 about half filled with 75 per cent alcohol. In addition to these 

 vials the collector should have a larger bottle and brush, similar to 

 the chloroform bottle described above. This bottle should contain 

 95 per cent of alcohol and 5 per cent of glycerin. The speci- 

 mens are killed by touching them with the brush moistened in the 

 95 per cent alcohol, after which they are washed off into the bottle 

 containing the weaker alcohol. The reason of this combination of 

 two grades of alcohol is that many insects are protected with a 

 waxy secretion which the weaker alcohol will not penetrate. Of 

 course, specimens should not be collected in this way unless they 

 are to be preserved permanently in some liquid medium. In collect- 

 ing some Thysanura it may be found necessary to dispense with 

 the glycerin, although it has a tendency to retain the color better 

 than the alcohol alone. 



Collecting forceps. \Yhile these are not absolutely essential to 

 the field kit, it will be found convenient to have a pair of stout, 

 broad-pointed forceps for handling stinging Hymenoptera, some 

 beetles, and other insects that are liable to injure the collector. 

 Fine-pointed forceps should also be taken along to handle very 

 small insects, although a moistened camel's-hair brush will serve 

 the same purpose. 



Hatchet and chisel. These tools will be found very useful in 

 collecting wood-boring insects and their larvae. The marble safety 

 ax stands in a class by itself, being far superior to anything else on 

 the market for this purpose. Even in general collecting this ax will 



