HOW TO KNOW THE INSEQS 



alcohol or they may be put at once Into the alcohol, which latter 

 method does not leave the specimen In as good condition. A little 

 glycerine, say 5 to 8%, prevents shrinkage and keeps the specimen 

 more lifelike. 



Some orders of water living Insects such as the May files and 

 stone files are so soft that pinning them Is not at all satis- 

 factory. They should be put up In vials of 80% alcohol or 4% 

 formaldehyde. The preservative should be changed after a day or 

 two for best results. 



Plant lice, thrlps, bird lice, sucking lice, and similar 

 small soft bodied Insects are mounted on microscope slides. Bal- 

 sam or Gum Dammar may be used. Berlese's Fluid* Is also good. The 

 locality data Is attached to one end of the slide and the name 

 label to i:he other. Some prefer to mount such Insects on small 

 bits of fairly thick cellulose acetate. (See Fig. 24) A small 

 cover glass and the Berlese Fluid are used the same as for the 

 microscope slides. These mounts are pinned at point height on an 

 Insect pin and labeled and otherwise treated like any other In- 

 sect mount. 



Caterpillars and other larvae are frequently Inflated. First 

 put them on a piece of blotting paper and press out the body con- 

 tents by rolling with a lead pencil or other cylindrical object, 

 starting from the thorax just back of the head and continuing to 

 the end of the abdomen, exerting just enough pressure to force 

 out most of the body contents and not enough to rupture the skin 



or break off the fine spines or 

 hairs. A piece of glass tubing 

 which has been drawn to a rather 

 long point Is then Inserted In the 

 anal opening of the caterpillar 

 and the caterpillar fastened to It 

 by a hooked wire clip on the tube. 

 Some collectors attach the skin by • 

 heating the point of the glass tube 

 before Inserting it. The wet skin 

 then adheres by its own juices to 

 the tube. The caterpillar skin Is 

 Inflated by forcing air by a hand 

 or "foot bellows Into the tube, care 

 being taken not to use too much 

 force and thus distort the cater- 

 pillar. While m this condition it 

 Is dried In an oven hot enough to 

 bake thoroughly without scorching 

 the Insect. Various types of appa- 

 ratus for inflating caterpillars 

 are to be had from entomological supply houses. The ingenious 

 collector, can easily make one for himself at little expense. All 

 that Is required is a lamp of some kind for heat, a tin can to 

 serve as an oven, a stand to support the can, glass tubing, a 

 bit of spring wire and a hand bulb or bellows. A rectangular 



*bistilled v/nter 20 cc 



Concentrated Glycerine 6 cc 



Gum Arabic .12 gms 



Chloral Hydrate 20 g:us 



Living insects may be mounted directly in this mer'ium. It is well to put them 

 first in water to prevent air bubbles. Alcohol specimens should be washed thorouphly 

 before mounting, 



31 



Figure 28, Method of mounting 

 inflated larvae. 



