[55] 



COLLECTING AND PRESERVING INSECTS RILEY. 



the most part stationary, being fixed to the plant by the protecting, 

 waxy, excretion or scale. The Flea-lice {PsylUdce) frequently produce 

 galls, and these should always be collected with the insect architects. 

 Some species do not pro- 

 duce galls, and may be col- 

 lected by sweeping. The 

 Hackberry is infested by 

 large numbers of species of 

 Psyllids, and these produce 

 a great variety of interest- 

 ing galls. The Aleurodidae 

 (Fringe-scales) are delicate 

 insects, and easily injured 

 in the taking; they are 

 therefore best reared from 

 their stationary and fringed 

 larv£e and pupse, which oc- 

 cur on the leaves of many plants. Leaves bearing the latter should also 

 be collected and pinned or preserved in alcohol. The Parasita, the 



Pig. 76. — The Bed-bug (Aeanthia lectularia). 

 adult — enlarged. 



Fig. 77 



-The Short-nosed Ox-louse (Hcematopinus eurysternus). a, female; 6, rostrum; c, ventral 

 surface, last segments of male ; d, female ; e, egg ; /, surface of egg greatly enlarged. 



lowest representatives of the order, may be obtained from the domestic 

 and wild animals which they infest. 



COLLECTING DIPTERA. 



Most Diptera frequent flowers and may be collected with a sweeping 

 net without much difficulty. The best season is from April to June, 

 and the bloom of the Willow, Alder, Plum, Cherry, Dogwood, Black- 

 berry, etc., will ordinarily yield a bountiful supply of specimens and 

 species. Parasitic and saprophytic forms may also readily be obtained 

 by breeding, the former as in the case of the parasitic Hymenoptera, and- 

 the latter from, decaying vegetable matter and fungi. The Diptera 



