120 ILLINOIS BIOLOGICAL MONOGRAPHS [120 



SUPERFAMILY SATURNIOIDEA 



Workers differ as to the number of families into which this group 

 should be divided, some defining the Saturniidae and Ceratocampidae, 

 others separating Hemileuca and a few related genera from the former 

 and calling them Hemileucidae. While the writer recognizes these three 

 families, the structure of the larvae compels him to differ from previous 

 workers and to include Automeris and Coloradia in the Hemileucidae. 

 The necessity for this change will be shown in a succeeding paragraph. 

 It is interesting to note that Miss Edna Mosher* found that the pupal 

 characters also relate Automeris more closely to the Hemileucidae than 

 to Samia and Saturnia. Whether specialists will later find that the 

 imagines justify this arrangement remains to be seen. 



The difference is emphasized by the basis of separation of the 

 Saturniidae from the Ceratocampidae. Forbes (1905), following Dyar, 

 uses for this purpose the scoli beta on the ninth abdominal segment, 

 which in Ceratocampidae are fused on the dorsomeson. He seems to have 

 overlooked the fact that such a fusion also occurs in Automeris (Fig. 109) 

 and other genera, with the result that these forms trace to Cerat- 

 ocampidae or Hemileucidae rather than to Saturniidae. 



Five types of arrangement of the scoli of segments 8 and 9 are found 

 in the superfamily and four of them are shown in the figures of Plate X. 

 In all five, scoli Rho and Kappa are normal on segment 8, and two similar 

 but more dorsally placed scoli of doubtful homology are found on 9. 

 Dorsad of these four are found the following modifications: (a) a single 

 mediodorsal scolus on 8, none on 9; (b) a subdorsal scolus on each side 

 on 8, none on 9; (c) a mediodorsal scolus on 8, and also one on 9; (d) a 

 mediodorsal scolus and pair of adjacent scoli on 8 and a mesal one only 

 on 9; (e) a mediodorsal scolus on 9, none on 8. The Saturniidae display 

 either (a) (Fig. 108) or (b) ; the Hemileucidae, including Automeris, 

 are armed as in (c) (Fig. 109) ; while the Ceratocampidae show either 

 (d) (Fig. 110) or (e) (Fig. 111). It is to be noted that Hemileuca, 

 Pseudohazis, Automeris and Coloradia are more similar to the Cerato- 

 campidae in the armature of these two segments than to the Saturniidae. 



The presence of scoli (Figs. 73, 74) distinguishes this superfamily 

 from all others except Nymphalidae and Heliconiidae. In the Saturni- 

 oidea, however, the head is never tuberculate nor horned and is always 

 more or less narrowed dorsad ; mediodorsal scoli, when present, are con- 

 fined to segments 8 and 9. The few difficult cases which remain are 

 discussed under Nymphalidae. The position and number of the scoli 

 differ so greatly that an extended diagnosis of the entire group on that 



*The Classification of the Pupae of the Ceratocampidae and Hemileucidae. 

 Ann. Ent. Soc. Am. 7, 1914, 277-300. 



