THE MONTHLY BULLETIN. 



MOUNTING. 



289 



There are various ways of mounting insects so as to show them off 

 to the best advantage, to preserve them longest and most perfectly and 

 to admit of their study. The most common methods are pinning 

 directly into suital)le cases, mounting in glass tubes or plaques, in 

 glycerine or balsam on slides and in alcohol or formalin in specimen 

 jars. All mounting work should be done as soon after the insects are 

 killed as possible, to avoid breaking the appendages. However, if they 

 are allowed to become dry and stiff they may be relaxed and safely 

 mounted by being placed for from twelve to forty-eight hours in a 

 moist chamber. In such cases care should be exercised to see that the 

 specimens do not mould. A piece of blotting paper in the bottom 

 treated with weak formalin will aid in avoiding this. 



Pinning. — Nearly all insects are pinned, especially the larger and 

 more chitinous ones, such as grasshoppers, beetles, true bugs, flies, 

 butterflies, bees, etc., but the position on the pin varies considerably. 

 All the members of certain orders are pinned, no matter how small, 

 while in many, the small chitinous ones are stuck on points which are 

 supported liy pins. The usual method of pinning insects is to thrust 

 the pin through the thorax, as shown in Fig. 290. All members of the 

 oiders Dipt era, Lepidoptera, Orthoptera, Hymenoptera (except the 

 exceedingly small forms), Neuroptera and Platyptera, are thus pinned. 

 The Orthoptera and many of the Hymenoptera are usually pinned 

 through the prothorax, while the others are pinned through the meso- 

 thorax. 



True bugs of the suborder Heteroptera should be pinned through the 

 scutellum, a small, usually triangular area just at the base of the 

 abdomen (Fig. 290 B). ' 



All beetles, except the small ones which are mounted upon points, 

 are pinned through the right elytrum or wing cover near the base, as 

 shown in Fig. 290 A and B. 



Secondary Pinning-. — Very small insects, especially Diptera and 

 Lepidoptera, are mounted upon exceedingly fine pins supported upon 

 one end of small pieces of pith, cork or cardboard, which are in turn 

 supported upon regulation pins at the other ends. This allows the 

 smallest specimens to be placed in the collection in a position not out of 

 harmony with the largest ones. 



Spreading. — Insects whose identity depends largely upon the vena- 

 tion and colorations of the wings are placed upon stretching boards 

 (Fig. 291 D and E) when fresh or relaxed and the wings properly 

 spread and allowed to thoroughly dry before they are placed into per- 

 manent cabinets. The hind margins of the front wings of a stretched 

 insect should be at right angles to the main axis of the body, as shown 

 in Fig. 291. 



Butterflies and moths collected in large numbers may be safely pre- 



13— H 



