PRESERVING 187 



The specimens are placed within it over night (or longer 

 if necessary), and the jar is closed with a lid. When again 

 flexible, the insects are pinned as when freshly killed. 



The best insect pins are \\" long, black, stiff, sharp-pointed, 

 with small round heads. They are thrust vertically through 

 the mesothorax in most insects, through the right wing cover 

 in beetles, leaving one-fourth of the pin exposed above the 

 back. Uniformity in position of specimen on the pins, adds 

 to the appearance of the collection, and depth-gauges of 

 various sorts may be used to secure it; but if, in pinning, 

 the pin head be grasped uniformly between thumb and 

 forefinger, and pushed through the insect into a cushion, 

 until the back of the insect touches the finger tip, a degree 

 of uniformity will be secured, and time will be saved. 



There are other ways of pinning insects when so minute 

 that the pins would split the bodies. Very small beetles are 

 glued to the points of elongate paper triangles, and the 

 triangles are then pinned. Minute Diptera are usually 

 mounted on pin points (slender pins cut to half length), 

 thrust upward through small pith or paper blocks, with 

 another larger pin through each block. 



Preservation in papers. — Dried specimens must not be 

 allowed to lie around over night exposed, else some of the 

 Tittle beetles that are museum pests may find them and lay 

 their eggs on them. Larvae, hatching from these eggs, will 

 quickly reduce the specimens to dust. Mice have destroyed 

 many a day's patient collection when left exposed. Speci- 

 mens put up in paper envelopes, or in layers between glazed 



