no Annals Entomological Society of America [Vol. III. 



two lengths. Xo caudal honi. Frontal punctures close together, 

 but the setae i are also close together. Mcnlum somewhat wider at 

 the base than one of the submenta. 



It may be distinguished from the Satumiidae by the much denser 

 hair on the maxillae, the larger front and the fact that setae a i of the 

 labium are much closer together. This genus is entirely isolated in 

 the North American fauna, it is perhaps most often placed with the 

 exotic family Eupte/otidac. 



Examples A. torrefacta I" igs. 54. oo and .30. 

 A. angelica. 



Lasiocampidae. 

 Very dense secondary hair on all parts except the tips of the palpi, 

 even on the antennae; tufts also present (/, Hi, iv and vii), but reduced: 

 front rather small, the punctures close together, and the primary setae 

 rather close together; adfrontals enlarged opposite top of front, with 

 the setae close together. Prolegs with hooks alternately of two lengths 

 in a single row. 



Second joint of antenna three times as long as wide. Labrum with 

 most of the secondary hair toward the tip of the lobes; prolegs s])read 

 laterally; a low tubercle in place of caudal horn; lappets on legless seg- 

 ments siinulating the legs, also on lirst segment each side of the head. 

 Example Artace punctistriga ?. 



Second joint of antenna twice as long as wide, labrum with most of 

 the secondary hair in the neighborhood of setae i and ii; no lappets or 

 tuV)ercles, prolegs normally placed. 



Examples Malacosoma americana. 



M. disstria (I'lgs. .".'.I and GO). 



Saturniina. 

 Secondary hair on epicrania, front and body, and sometimes on 

 adfrontals, mandibles, maxillae, and labium ; tubercles, at least in part 

 with tufted hair; tubercles ii of either eighth or ninth abdominal seg- 

 ments fused across the middle line (that of the eighth would be the 

 caudal horn), except in Satumia; mentum wide, its base wider than 

 one of the submenta; prolegs with hooks alternately of two lengths, 

 in a single band; setae ai of labium far apart; punctures of front far 

 apart, with reference to the setae, but close together in comparison to 

 the width of tlic front. 



Ceratocampidae : Tubercles ii of ninth al)dominal segment fused. 



Adfrontals, maxilhc and labium without secondary hair; front as wide 

 as high and head wide; u of adfrontals about 12-5 up the front; clypeal 

 setcC close together; secondary hair of body minute; armed with many 

 long horns. 



Example Citheronia. Fig. 63. 



Maxilkf with secondary hair but none on adfrontals; front wider 

 than high, u of adfrontals only l-'.i way uj) it ; clypeal setae close together; 

 head as wide as high; scccmdary hair of body long. 

 Example Basilona. Figs. Gl and G5. 

 Maxilhc, adfrontals and labium with secondary hair: head and front 

 both higher than wide; adfrontals wider; both v and vi of labrum distant 

 from margin; secondary liair of body minute. 



Example Anisota. Figs. 02 and 04. ^ 



