170 INSTRUCTIONS FOR COLLECTING INSECTS. 



"be cut with ordinary scissors into pieces of proper length and taken 

 with you. The wire must be inserted into the insect by means of a 

 very delicate pincers, and with the same instrument the other end of 

 the wire must he stuck into a hox, the bottom of which is covered 

 smoothly with the pith of plants. Over the pith thin paper may be 

 fastened in order to render the surface still more smooth. The top or 

 cover of the pill box, in which the insects are placed while transfix- 

 ing them, must not be too shallow, so that they may not be blown 

 away by the wind, if the operation is performed in the field. The use 

 of a glass vial for the capture of small insects is not to be recommend, 

 as the moisture separates their parts and thus spoils them. The vial 

 may be used on excursions, when you desire to take home a single 

 living insect for the purpose of examining the organs of its mouth or 

 its internal structure. 



Those specimens which have been transfixed on the silver wire, as 

 above indicated, are prepared for the collection in the following way : 

 In the fall, stalks of weeds with pith not too porous, and before it is quite 

 dry, must be collected. The best adapted for this purpose is the pith of 

 Artemisia, and, still better, of Verhascum, (mullein.) It is cut into small 



Fig. 3. .1 n pieces, which, seen from above, have the form and size of 



Fi 4 ] ^ fig. 3, and seen from the side the thickness of fig. 4. Then 



" ^ insect pins of moderate size are inserted through these 



Fig. 5. small pieces at the place indicated by the dot, (fig. 5,) and the 

 pieces are pushed up nearly to the ])in's head. As the pith 

 is still moist it will adhere to the pin in drying, and by the 

 slight coat of verdigris which will soon be developed, the 

 insects, which have been previously attached to the silver wire 

 are now inserted on the free end of the pith with the delicate 

 pincers, where they will stick fast enough if the proper kind 

 of pith has been used. Pith of Samhucus, or elder, Edianthns, 

 or sunflower, and similar plants, do not answer the purpose, 

 because it is too porous. The insect should stand a little 

 higher than the head of the pin, so that it may be conve- 

 niently examined from all sides. The silver wire used for this purpose 

 should be of the very best quality so as to prevent the development 

 of verdigris. 



In regard to the Tipularia, and some others, whose legs easily break 

 oft', my method is the following : I capture them with the forceps and 

 pin them as other large specimens. Before pinning, I press the thorax, 

 so as to prevent all struggling ; I then stick the pin through a piece 

 of paper of this form, (fig. 6.) and push it up far 

 enough to receive the legs of the insect neatly spread 

 out or turned under it. When the insect is dead I 

 remove the paper, which, however, might as well 

 be suffered to remain. 



The boxes in which Diptera are kept should be 

 about a foot square, the top should be glass, and 

 made to fit tight to the other part by a double rab- 



