NEUROPTERA 



297 



The larvas of the hemerobiids, as far as they are known, resemble 

 in their general appearance aphis-lions (Chrysopidae) , and, like the 

 aphis-lions, feed on 

 plant-lice and other 

 small insects. Their 

 mouth -parts are 

 formed for piercing 

 and sucking (see 

 page 282), and the 

 posterior part of 

 the alimentary ca- 

 nal is transformed 

 into a silk-organ, as 

 in Sisyra (see page 

 283). They are 

 found most often 

 running about on 

 trees, and especial- 

 ly on coniferous 

 trees. Some, like 

 the aphis-lions, are ^% 

 naked ; but the lar- 

 vae of some species, 

 at least, of Hemcro- 

 hius cover them- 

 selves with a cloak, composed of the empty skins of their victims 

 and other debris (Fig. 335). These larvae are furnished at the sides 

 with projections which serve as pedicels to elongate, divergent hairs 

 that help to keej^ the cloak in place. 



There are thirty described American species belonging to this 

 family; these represent four genera, Hemerobius, Boriomyia, Megalo- 

 mus, and Micromus. 



Family DILARIDyE 



335. — Larva of Hemerobius: A, the larva bare; 

 B, the same partially concealed by the remains of its 

 victims, etc.; a portion of the covering has been re- 

 moved in order to show the head. (From Sharp.) 



The Dilaridse is a small family, representatives of which are found 

 chiefly in the Old World. In this family the antennas of the male 

 are pectinate ; and the female is furnished with an exerted ovipositor. 



Only a single, exceedingly rare species, Dllar americdnus, has been 

 foimd in North America; and of this only a single female individual 

 is known. This is a small insect ; the length of the body, not includ- 

 ing the ovipositor, is about 3 mm.; the length of the ovipositor is a 

 little greater than that of the body ; the expanse of the wings is about 

 1 4 mm. There is a single five-branched radial sector in both fore and 

 hind wings. In several exotic species the radius of the fore wings 

 bears two or more sectors. 



The type of our species was taken at Bee Spring, Kentucky, in 

 June, 1874. 



