60 



Lottin: Introduction 



soft block or inverted cardboard box lid \ f-Y 



Intro, fig. 88. Position of pins for different insects (Ross, 1953). 



DAMSEL FLY 



be buried deep in the soil and away from human 

 habitations. 



Safer killing bottles can be made by using ethyl 

 acetate, carbon tetrachloride, or chloroform as the 

 toxic agent. These materials may be poured onto a 

 matrix of plaster of Paris or tightly packed paper 

 and the bottle may be recharged as needed. 



Specimens should be removed from killing bottles 

 as soon as possible and not later than the end of the 

 day of collection. Delicate insects such as mosquitoes 

 should be transferred to small pill boxes while still 

 in the field. Larger insects such as beetles or scaly 

 insects such as moths should never be placed in 

 the same bottles with fragile forms. 



Mounting and storage of material. — Insects killed in 

 the field should be mounted on pins or points while 

 still fresh and soft. However, this is sometimes 

 impractical on extended field trips. If specimens 

 are to be held unmounted for more than a few hours 

 they should be placed between layers of cellucotton 

 in cardboard or wooden boxes (cigar boxes are satis- 

 factory) or between cellucotton or soft tissue paper 

 in pill boxes. Dragonflies are best handled in paper 

 triangles (intro. fig. 86). Crystals of paradichloro- 

 benzene or naphthalene may be added to repel der- 

 mestid beetles and other museum pests. In the tropics, 

 silica gel or some other dehydrating agent should be 

 used in airtight containers to prevent formation of 

 mold. 



In the laboratory, dried material is softened in a 

 "relaxing jar" (intro. fig. 87) before mounting. This 

 jar should have a wide mouth to facilitate handling 

 of specimens. A layer of moist sand is placed on the 

 bottom, and a small amount of carbolic acid is added 

 to prevent the growth of fungus. A piece of hardware 

 cloth is bent down at the sides and placed on the 

 sand to prevent the specimens from coming in direct 

 contact with water. The specimens are placed on 

 the screen and the top is closed tightly. Within twenty- 

 four hours the specimens will be soft. 



Fresh or "relaxed" specimens are usually mounted 



on pins that are especially designed for the purpose. 

 These may be obtained from most biological supply 

 houses. They are longer and thinner than common 

 pins and are black with gold heads. No. 2 pins are. 



Intro, fig. 89. Two types of spreading boards showing technique 

 of preparation; a, block for very small insects; b, typical board 

 for larger Lepidoptera and Odonata (Oman and Cushman, 1946). 



