60 COLLECTING AND PRESERVING. 



for some Doleri and Nemati, and in woods containing 

 oaks, birches, willows, and poplars. The sweeping 

 net is of most use during the day when beating, 

 especially if the day be bright and warm, produces little, 

 for they fly away the moment the trees are touched. 

 If the weather be dull, however, beating may be 

 employed advantageously, as it can always be done in 

 the evening. 



They maybe either pinned or mounted on cardboard. 

 If pinned, and not set properly, the wings should be 

 separated in such a way that the neuration can be 

 easily examined. If the carding method be followed, 

 the insects should be mounted in such a way that the 

 form of the clypeus can be seen, and the hinder tarsi 

 should be loose, so that the form of the claws can be 

 conveniently seen. It is better, too, to have at least 

 one specimen with one wing not gummed down. 



The saws are best prepared for microscopical exami- 

 nation as follows : They are extracted from the 

 abdomen by pressing its sides, when they will project, 

 and be easily cut off. The pieces should then be 

 separated and steeped in turpentine for a day or two. 

 Take a sheet of thin Bristol board, cut it into pieces, 

 say six lines by nine, then punch in one end of this a 

 round or square hole, say two and a half lines across. 

 Next, fasten to one side of this hole a microscopic 

 cover glass by means of Canada balsam dissolved in 

 benzine. After this has dried, fill up half of the cell 

 thus formed with balsam, spreading it as evenly as 

 possible. In this arrange the parts of the saw, set the 

 preparation aside for a day, then fill up with balsam 

 until the cell overflows, and put on another cover glass. 

 All that now remains to be done is to keep the pre- 

 paration in a flat position until the balsam has dried, 

 after which it is labelled and a pin stuck through 

 the cardboard, by means of which it is placed in the 

 cabinet along side the insect from which the saw was 

 taken. 



For the examination of the saw a quarter-inch 



