1893-] ENTOMOLOGICAL NEWS. 39 



ELEMENTARY ENTOMOLOGY. 



LEPIDOPTERA-HETEROCERA (Moths). 

 By Prof. JOHN B. SMITH, New Brunswick, N. J. 



The Saturniidae and Ceratocampidae differ from all the other 

 of our Bombyces by having the antennal joints unusually long, 

 and furnished with two pectinations to each side. Each segment, 

 therefore, bears four branches or joints. This structure is not 

 paralleled elsewhere in the Lepidoptera, so far as my knowledge 

 extends, except in the aberrant Sphingid genus Cressonia. Its 

 distinctive character gives it an absolute systematic value, and by 

 its aid all members of these families may be readily recognized. 

 Between themselves, the Saturniidae and Ceratocampidae differ, 

 primarily, in that the former have the antennal pectinations ex- 

 tending to the tip, while in the latter they extend only a little 

 beyond the middle. 



In the Saturniidae the head is small, and the ocelli and tongue 

 are wanting. The venation is quite simple, and usually the pri- 

 maries have ten veins only; the missing veins belonging to the 

 sub-costal series. In the fore wings there is one internal vein, 

 which may or may not have a small fork at the base. The cell 

 extends to the middle of the wing or beyond it, and the veins are 

 well separated. The secondaries lack all trace of a frenelum in 

 both sexes; the costal vein is free from the base, and there are 

 two internal veins, the inner very feeble and very close to the 

 internal margin; vein five belongs to the sub-costal series. The 

 legs are short and very hairy, the tarsi very feebly spinulose. 

 The little epiphysis on the underside of the fore tibia is distinctly 

 present. 



It is to this family that our American "silk worms" are re- 

 ferable; and the moths are the giants among our Bombyces; ex- 

 panding in some instances six inches or more. 



Two very well separated sub-families are recognizable: the 

 Attacinae and Saturniinae, recognizable primarily by the fact that 

 in the Attacinas the median cell on both wings is open, while in 

 the Saturniinae it is closed by a distinct cross-vein. Other dif- 

 ferences exist: in the Attacinae the antennal development is most 

 perfect, the pectinations being as complete, though smaller, in 

 the female than in the male. The wings are verv broad, the pri- 



