I 20 Annals Entomological Society of America [Vol. Ill, 



or with i)nniary hair only, when there is tufted hair tliere are only 

 two warts on the abdomen above the spiracle. Prolegs with 

 hooks not alternately of the two lengths, or without prolegs. 



Heterogynidae: With primary hair only; prolegs with a single 

 nomial band of hooks; head black and heavily chitinized; epicrania 

 with a deep cleft at the vertex; front with the punctures decidedly 

 nearer the corresponding setae, than to each other; labrum with ii 

 strong, and no higher than i: antenna normal; body with i and ii well- 

 separated, iv and v approximated, two setae on a level, in the position 

 of vi, but one on the outer side of the proleg, and two on the inner side. 

 It seems clear that the anterior seta on the inner side of the proleg 

 belongs to vii, but more doubtful whether the additional seta in the 

 position of vi is the other missing one. 



Example Heterogynis paradoxa. 



Zygaenid.\e: Head as in the preceding, seta ii of the labrum 

 decidedly higher than i, but fully developed; body with somewhat 

 diffuse tufts of hair, representing, i+ii, Hi, iv+v, vi, and two tufts 

 representing vii; viii single-haired; hair serrate, but not feathery. 

 K.xaniple Zygaena trifolii. 



Megalopygidae: Head pale, and lightly chitinized, submenta 

 membranous; epicrania with the cleft in the vertex filled up, apparently 

 by the growing together of its edges; their setae rudimentary; labrum 

 with ii higher than in Zygacnidae, much smaller than i, none of the 

 setae marginal ; frontal punctures rather nearer to each other than to 

 the corresponding setae; antenna with first joint about as long as sec- 

 ond, second less than twice as long as wide and without any long seta. 

 Body with tufts as in Zygaenidae, but in addition with two isolated 

 setae on a hump, near the tip of the prolegs. The row of hooks on the 

 ventral prolegs is angulatc in the middle and the shortest hooks come 

 next to the angle, viii is opposite the apex of the angle. Second and 

 seventh abdominal segments with rudimentary prolegs, on which the 

 setae are arranged as on the normal ones, but without any hooks. 



Hxamjjle Lagoa crispata. I-'iij^s li':!. 12 4, 12.">, lL*() and 135. 



Eucleidae: Mostly like the preceding family. Hair more or less 



reduced, diffuse, modified into branching spines, or absent;* without 



prolegs, and without setae on the ventral jiart of the body; with a row 



of ventral suckers. 



Examples Cnidocampa flavescens. 

 Empretia stimulea. 

 Euclea delphinii. 



NOLIDAE. 



With tufted, hut no secundar.\- hair. Epicrania, front and 

 clypeus as in the Eucleidae, but with normally developed setae. 

 Labiimi with setae normal, i h'ing between setae ii, and nearly on 



♦ See Dyar. Joum. N. Y. Ent. Soc., vols, iii to vii for details of structure of the various species. 



