[59] 



COLLECTING AND PRESERVING INSECTS RILEY. 



renders their collection an easy matter. Effort, however, sbonld be 

 made to discover the different forms, the females and soldiers as well as 

 the workers. The former may be found in rot- 

 ten tree trunks, but are very rarely met with. 

 In the trox)ics many species occur and construct 

 curious nests, either attaching them to the 

 l)Oughs of trees or building them in the form of 

 j)yramids on the ground. The Dragon-flies {Li- 

 hellulidce,) are collected in the same way as the 

 Diurnal Lepidoptera. They are very swift 

 flyers, and are i^ractically always on the wing. 

 Their collection requires some degree of skill 

 in the use of the net. A good method consists 

 in visiting, in the early morning, water courses 

 in which the larval and i)upal states are passed, 

 and capturing the adults just as they issue from 

 their pupal skins at the edges of the pond or 

 stream. In cold weather they are less active 

 and may frequently be found clinging to trees 

 and plants, particularly in the vicinity of their 

 breeding places. May-flies {JEphemeridce) occur 



in immense 



numbers 



near their 



breeding 



])laces in Fig. 85.— b, a Mny-Qy (PaUnge- 



nonds auf] niabUneata); c, its laxvn; a, a. 



Caddis-flv (Macronema zebra- 



streams and tum). 

 are also attracted in large quantities 

 to electric lights. Their collection 

 is therefore an easy matter, but on 

 account of the very fragile nature of 

 these insects the utmost care must be employed in handling them. The 

 €arly states of all the aquatic forms mentioned above may be obtained 

 for breeding by the use of the dip net by dragging 

 it forcibly against water i^lants. 



Weuroptera proper (Hellgrammites, Lace-wings, 

 Ant-lions, Caddis-flies, etc.) — Among the larg- 

 est insects of this order are the Sialidoe, w^hich in- 

 cludes the enormous Hellgrammite Fly, Corydalus 

 wrnutus. The larvse of this insect are carnivorous 

 and occur in streams, under stones, etc. The 

 adults may be collected in neighboring situations 

 and are also attracted to light. The Lace-wing 

 flies {Chrysopa), Ant-lions, etc., are carnivorous as larvae, and occur, 

 the former among the Aphides which infest various plants and the latter 



I'm. 



5. — A Dragon-fly (Libellula) . 

 Packard.) 



(From 



Fig. 87.— a Dragon-fly 

 (Agrioii). (From Pack- 

 ard.) 



