94 THE CLASS OF INSECTS. 



P, P, upper and under sheets of paper ; C, space between 

 lower sheet of paper and liottoni of box." 



Other substitutes are the pith of various plants, especially 

 of corn ; and palm wood, and "inodorous felt" is used, beinij; 

 cut to fit the bottom of the box. 



Leconte recommends that "for the purpose of distinguish- 

 ing specimens from different regions, little disks of vai'iousl^' 

 colored paper be used ; they are easily made by a small punch, 

 and should be kept in wooden pill-boxes ready for use ; at 

 the same time a key to the colors, showing the regions em- 

 braced by each, should be made on the fly-leaf of the catalogue 

 of the collection." He also strongly recommends that the 

 "specimens should all be pinned at the same height, since the 

 ease of recognizing species allied in characters is greatly in- 

 creased by having them on the same level." 



He also states that "it is better, even when numbers with 

 reference to a catalogue are employed, that the name of each 

 species should be A\Titten on a label attached to the first speci- 

 men. Thus the eye is familiarized with the association of the 

 species and its name, memory is aided, and greater power given 

 of identifying species when the cabinet is not at hand." For 

 indicating the sexes the astronomical sign ^ (Mars) is used for 

 the male, and 9 (Venus) for the female, and 9 for the worker. 



Transportation of Insects. While travelling, all hard-bodied 

 insects, comprising many Hymenoptera, the Coleoptera, Hc- 

 miptera, and many Neuroptera should be thrown, with their 

 larvjfi, etc., into bottles and vials filled with strong alcohol. 

 "VVlien the bottle is filled new liquor should be poured in, and 

 the old may be saved for collecting purposes ; in this way the 

 specimens will not soften and can be preserved indefinitely, and 

 the colors do not, in most cases, change. Leconte states that 

 "if the bottles are in danger of being broken, the specimens, 

 after remaining for a day or two in alcohol, may be taken out, 

 partially dried by exposure to the air, but not so as to be brit- 

 tle, and these packed in layers in small boxes between soft 

 paper ; the boxes should then be carefully closed with gum- 

 paper or paste, so as to exclude all enemies." 



Lepidoptera and Dragon-flies and other soft-bodied insects 

 ma}- be well preserved by placing them in square pieces of pa- 



