

COLLECTING AND PRESERVING INSECTS — BANKS. 53 



Alcohol may be used to capture many wingless insects, such as 

 springtails, myriapods, spiders, larvae, etc., but adult insects should 

 not be collected in it unless nothing better can be secured to kill 

 them. Even for larvae it is better to bring them home in tin boxes 

 and kill and prepare them in other ways. Alcohol should not be 

 used at full strength, but about 70 per cent is sufficient for most 

 purposes. A little glycerin in the alcohol is an advantage, since if 

 the bottle cracks, or the alcohol evaporates, the glycerin will keep 

 the specimens moist for a long time. It is claimed by some that 

 specimens killed in alcohol are less liable to verdigris, but the use of 

 black pins obviates this danger. 



Very large insects may be killed by injecting into their thorax a 

 little kerosene; some have used benzine or gasoline to kill Lepidop- 

 tera in the field, squirting it upon the specimen by means of a drug- 

 gist's dropping tube. Other collectors have used creosote for killing 

 specimens. This, however, will not last more than a few days. Some 

 entomologists have used ammonia for killing microlepidoptera, but 

 it is liable to change some of the delicate colors. All things consid- 

 ered, the use of the cyanide jar is far superior to other methods. 



PINNING INSECTS. 



Entomologists mount their insects on pins especially made for the 

 purpose. These are more slender and longer than the ordinary pin, 

 and can be bought from all dealers in entomological supplies. As 

 they are now comparatively cheap, all beginners should use them. 

 The price averages about $1 a thousand; many are cheaper. They 

 are made both bright and japanned or black. Some are of steel, and 

 these are not as flexible but keep the point well. 



These pins are made in different sizes or numbers, from 000, the 

 most slender, up to No. 8, the thickest. The sizes below No. 1 are 

 usually too small for satisfactory use, as they will not readily enter 

 cork. They are useful, however, in making elbow pins, as explained 

 later. Likewise the pins over No. 4 in size are too large for most 

 insects, and should only be used for insects of extraordinary size. 

 The best size for general use is a No. 2; for smaller insects a No. 1, 

 and for larger, a No. 3. Many lepidopterists use a No. 3 for most 

 specimens and No. 4 for larger forms. Some orthopterists use a No. 4 

 for most species. However, the No. 3 will carry well an insect of 

 almost any size ; and the use of larger pins is apt to result in destroy- 

 ing too much of the thorax. A No. 2 is best for beetles, Hymenop- 

 tera, Hemiptera, and flies; a No. 3 for the larger species, and a No. 1 

 for small forms. Many coleopterists, however, prefer to mount on 

 points all beetles too small for a No. 2 pin. 



Each entomologist has a different opinion as to the limits of use of 

 each size, but the general tendency is that Nos. 1, 2, and 3 will cover 



