HOW TO KNOW THE IMMATURE INSECTS 



49a. With eversible mid-dorsal glands on 2nd abdominal segment. 

 Fig. 481 Family LYMANTRIIDAE 



The caterpillars of this compara- 

 tively small family are usually 

 clothed with long hair-like scales 

 which are often sting producing. 

 They feed on the foliage of forest 

 trees. 



Tus'dA)^°^°'°^^''' antique L. 



49b. No eversible mid-dorsal glands 50 



50a. Spiracles circular, small Family PTEROPHORIDAE 



50b. Spiracles elliptical, normal in size 51 



51a. Wart or seta iv much lower on 7th abdominal 

 segment, or absent. 

 Fig. 482 Family NOCTUIDAE 



Fig. 482. Setal 

 mop of 6th, 7th 

 and 8th ab- 

 dominal seg- 

 ments. 



51b. Wart or seta iv about the level on 7th abdominal segment as on 

 the 6th and 8th ..Family ARCTIIDAE 



52a. Body without noticeable secondary hairs; with not more than 8 

 hairs on each proleg (Etbmia) Family ETHMIIDAE 



52b. Body with numerous secondary hairs, at least on the prolegs. .53 



53a. Setae very irregular in length, some ten times as long as the 

 others; with obscure warts, at least in the earlier stages; some- 

 times provided with scale-like hairs. 

 Fig. 483 Family LASIOCAMPIDAE 



About 1,355 species have been 

 scribed. The canterpillars pos- 

 sess long hairs and are brightly 

 colored. They live in forested 

 areas and orchards and feed 

 on the foliages of various trees. 

 The tent caterpillars, Malacoso- 

 ma spp. occur in large numbers 

 and lie in webs. The Syrian 

 silkworm, Pachypasa oius Dru- 

 ry belonging here was reared 



Fig. 483. Molocosomo americano 

 Fab. 



for its silk by the Greeks and Romans. 



169 



