59 

 Lattin: Introduction 



which are altered beyond recognition in alcohol, or 

 which, by tradition, have always been mounted on 

 jins or points. When collecting for an entomological 

 nuseum an entirely different approach is necessary, 

 [n many groups, such as the moth flies (Psychodidae), 

 adults should be collected and preserved both wet 

 and dry, in split series. Parallel collections of this 

 kind make it possible to study color pattern and 

 pubescence on dry specimens and structural details on 

 specimens in alcohol. Dried material is very fragile 

 and requires constant care to guard against breakage 

 and damage from museum pests. Collectors and admin- 

 istrators of collections should be prepared to care 

 for scientific collections or should see that they are 

 placed in a museum where they will be preserved 

 and made available to others. 



i Alcohol vials. — The aquatic stages of nearly all 

 insects are best collected and preserved in vials of 

 70 or 80 per cent ethyl alcohol. This fluid penetrates 

 and preserves all but the most fleshy larvae and has 

 none of the undesirable characteristics of formalin. 

 As a convenience in handling and in storage only 

 two or three sizes of vials should be used. Two-dram 

 homeopathic (lipped) vials are very satisfactory for 

 general collecting. Smaller vials of a diameter similar 

 to dental procaine tubes came into general use during 

 World War II and are now used extensively for collect- 

 ing and storing very small insects. Stoppers should 

 be of synthetic rubber, rather than cork, so as to 

 prevent drying, shrinking, and evaporation. Alcohol 

 should be changed within a few days after collecting 

 because it becomes diluted with water and body fluids 

 of the specimens. Large beetles, bugs, and Mega- 

 loptera larvae should not be placed in the same vials 

 with delicate specimens. White, fleshy crane fly 

 larvae and caterpillars should be killed quickly in 

 boiling water before preserving in alcohol. This 

 fixes the body proteins and prevents decomposition 

 and blackening of specimens. 



If a collecting vial contains more than one species, 

 the material should be sorted in the laboratory to 

 facilitate future arrangement in a collection. Sorting 

 may be done in a white enamel pan, petri dish, or 

 some other convenient flat container. After sorting, 

 each vial should be labeled with full data as to 

 locality, date, collector, and field notes or notebook 

 number. Labels should be written in India ink on 

 good grade bond paper. 



pled 



ter of Pons 



sawdust 



powdered cyontde 

 or plaster of Ports saluroted with 

 corbon tetrachloride or ethyl acetate 



Intro, fig. 86. Technique of folding paper triongles for insect 

 storage (DeLong and Davidson, 1946). 



Killing bottles. — Most adult insects collected on 

 land or in the air should be killed in a cyanide bottle 

 or other dry container. Exceptions are the stoneflies, 

 caddisflies, and mayflies which are better preserved 

 in alcohol. A cyanide bottle (intro. fig. 85) contains 

 crystals of calcium, sodium, or potassium cyanide 

 covered by sawdust and held in place by a layer of 

 plaster of Paris. A small amount of moisture is 

 sometimes necessary to activate the cyanide, but 

 usually the problem is too much rather than too 

 little water. Absorbent tissue should be placed in 

 the bottle to remove excess moisture and to prevent 

 fragile insects from damaging each other. Cork stop- 

 pers should be used rather than screw tops because 

 the latter are inconvenient or difficult to manipulate 

 while collecting. The lips and bottoms of cyanide 

 bottles should be taped to reduce the chances of 

 breakage or air-tight plastic bottles may be used. 

 Cyanide is, of course, a deadly poison and must be 

 used with great care. If a bottle is broken it should 



tight lid 



insects 



wire net 



damp sawdust 



Intro, fig. 85. Details of cyanide bottles (Ross, 1953). 



Intro, fig. 87. Relaxing jar used to soften insects for 

 mounting (Ross, 1953). 



