408 



INJURIOUS AND BENEFICIAL INSECTS OP CALIFORNIA 



with the surface. The bait is suspended just over the mouth and the 

 approaching insects fall into the pit and are unable to escape. 



KILLING 



Insects to be mounted and preserved 

 collected as possible. The most popular 



Fig. 494. — Pinned insects. A cicada pinned 

 the mesothorax at the top and two bugs pinned 

 the scutellum at the bottom. (Original) 



are also excellent containers, as they e 

 poor fitting of the lids, however, they 



should be killed as soon after 

 method of killing is the use of 

 a jar or can containing 

 potassium or sodium 

 cyanide. The cyanide 

 may be kept in the bot- 

 tom of the jar or can 

 Math plaster Paris, or 

 better, with suitable 

 pieces of blotting 

 paper, which absorb the 

 in o i s t n r e. The lid 

 should be tight, so as 

 to retain all of the 

 fumes, and enough 

 cyanide used to make 

 the killing rapid. Small 

 killing-vials, suitable 

 for the pocket (Fig. 

 491 ) , are very desirable 

 and easily made. 

 Baking powder cans 

 an not be broken. Due to the 

 need often to be refilled. In 



through 

 i hrough 



Fig. 41)5. — Pinned insects. Beetles, all pinned through the bases 

 of the right elytra. (Original ) 



preparing such a can, cut a circular piece of blotter to cover the bottom ; 

 add the cyanide and pack cotton or other material tightly around it ; 

 cover all with several circular, tight-fitting pieces of blotter, and then 



