OUTLINES OF ENTOMOLOGY. 127 



streams. They feed upon small water insects and vegetation. Prof. 

 Comstock describes a species that makes a very simple case under 

 stones in rapid streams, but excites much admiration by its ingenuity 

 in fishing, catching its prey by means of a seine-like web stretched be- 

 tween two stones. 



The Ant-lions (genus Myrmeleon) are very delicate and beautiful 

 flies, with slender bodies and oblong, lace-like wings, sometimes plain, 

 sometimes ornamented with black dots (see lower figure in plate). 

 They have a graceful flight, and are occasionally attracted into our 

 lamp lighted rooms at night. The larvte are ugly and ferocious look- 

 ing. The body is rough and broad-oval in shape, and the flattened 

 head is provided with a proportionately enormous pair of pincer-like 

 mandibles, adapted for seizing and holding its victims while they are 

 pierced and comminuted by the maxilhie. These larva? dig funnel- 

 shaped or saucer-shaped pits in sandy soil, with a straight shaft in the 

 center in which they hide, supporting themselves with the tips of the 

 gaping jaws just above the edge, ready to close with lightning-like 

 rapidity on any unlucky ant or other insect that carelessly strays over 

 the edge of the pit-falls and slides into the trap at the bottom. If the 

 insect obtains its footing and attempts to crawl up the steep sides it 

 is brought down with showers of sand thrown upon it by the enraged 

 and disappointed ant-lion, and it is but very raiely that it escapes. 

 These larvas are called "doodle bugs" in some parts of the country, 

 and are most commonly found on the margins of streams and in shel- 

 tered ravines. [Fig. 48.] 



The Lace-wing flies are another small 

 group of terrestrial Neuroptera. They 

 are pretty but fragile and ill-odored flies, 



Lace-wing fly (Chrysopa) and egg j on , j, • 



stalks, after Riley. of a pale green or rosy hue, the wings re- 



flecting prismatic colors. The antenniiB are thread-like and nearly as 

 long as the body, and the round eyes gleam like jewels. The oval pale 

 green eggs arc laid in clusters, each attached to the top of a slender 

 silken stalk. This is supposed to be a precautionary instinct of the 

 parent fly to preserve them from the rapacity of the larva that hatches 

 first. The larvie are called "Aphis-lions" from the small insects which 

 are their more especial prey. They are of depressed oval form with 

 pincer-like jaws and long, rather sprawling legs. They render valuable 

 aid to the farmer and horticulturist in clearing his trees and other 

 plants of plant lice, bark lice and similar small pests. When full grown 

 they enclose themselves in round white cocoons, which are closed on 

 top by a lid that is easily pushed up when the fly is ready to emerge. 



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