16 PACKARD. NOTES ON 



verging towards the front edge which is very straight, with the 

 edge slightly re volute. Its surface is convex, often remarkably 

 so, sometimes ending in a large mesial tubercle. The mouth 

 parts do not afford good family characters in distinction from 

 the Sesiidsa and the higherBombycidse the mandibles are slen- 

 der, curved, with dense setae applied upon the well developed 

 maxillae. Labium small equilaterally triangular. However 

 there is a distinct form of the maxillary palpi, which are long, 

 slender, acute, slightly ascending, but porrect ; the third joint is 

 long, acute, thinly scaled, and very free from the head ; the 

 first and second joints very equal in length, and with long thin 

 scales beneath. 



Thorax moderately stout, longer than broad. The pro-thorax 

 is well developed, especially the scutum (collar), the two halves 

 of which are partly separate, large suborbicular, and often gaily 

 colored. The mesoscutum is small, quadrangular, shorter than 

 broad, the sides bent down angularly under the patagia. which 

 are half as long as the meso-thorax in Zygasna, but more gener- 

 ally much longer. Scutellum nearly as long as broad, lozenge- 

 shaped, the posterior half longer, being more produced than the 

 anterior half. The meta-thorax much as usual, though the 

 scutellum is a little longer and more elevated than in the other 

 families. The flanks cannot be properly described without alco- 

 holic specimens, however, they are slightly inclined the middle 

 flanks occupy more than half the lateral surface of the whole 

 side of the thorax, while the hind flanks are one fourth to one 

 half as broad as the middle ones. Wings long and narrow, 

 though often triangular, with very short nervules one third as 

 long as the wing. The primaries equal the body in length ; they 

 are nearly three times longer than broad, while the costal and 

 inner edge are more parallel than in the other moths, except 

 the .ZEgeriadse. Costa straight, apex much rounded ; outer edge 

 full, half or two-thirds as long as the inner, internal angle well 

 rounded. The costal space is narrow. The nervules more gen- 

 erally arise far beyond the middle of the wing, and are of very 

 equal lengths, thus making their interspaces very equal. The 

 s.c. nervules are unusually short, especially the fourth, while the 

 fifth equals in length the median nervules. Both the subcostal 

 and median nervules curve inwards and throw off the discal 

 nervules at opposite points, which are together curved very 

 regularly inwards, thus making the discal space which is nar- 



