no. i. BOMBYCLNE MOTHS OF NORTH AMERICA— PACKARD. 3 



claspers of the lower pair at base not differentiated from the upper claspers, incurved, blunt 

 at the end, which does not extend beyond the outer fourth of the length of the upper claspers. 



Geographical distribution. — The species range from Mexico to Brazil, being characteristic 

 neogseic forms. 



Larva. — The full-fed larva? of this genus, as in Aglia tau and Cercophana, are unarmed, with- 

 out any characteristic humps or spines, while the fresldy hatched larva? entirely differ in bristling 

 with forked spines or flexible horns, these characters not being thrown off until the last ecdysis. 



Stage I. — Two large 5-headed pro thoracic dorsal setiferous spines; mesothoracic dorsal 

 spines reduced, minute, while those of the third thoracic segment are enormous, about half as 

 long as the body, flexible, forked at the end; caudal horn in shape like the metathoracic ones, 

 but about one-third as long. The long setae arising from all the tubercles are black and 

 spinulose. 



Later stage to the last molt. The partly grown larva, when about one-half grown, is 

 drawn as having a pair of high horns on the prothoracic and a longer pair on the third thoracic 

 segment, and a caudal hom on the eighth segment, also a shorter median horn on the ninth 

 abdominal segment. Peters l states that this armature is retained until the last molt. Here- 

 tofore we have only had the figures of the mature larva of three species of this genus, and four 

 sketches of the caterpillar of A. armida, the better known species of tliis interesting genus, 

 which ranges from Mexico to Brazil. The larva figured by Madam Merian, Stoll, Burmeister, 

 and by Peters, is represented as being smooth, without any tubercles, horns, or hairs. 



Fully fed larva. — Either without any spines or tubercles, the body being smooth, unarmed, 

 and of a generalized form (A. armida), or apparently the four thoracic and the caudal horn of 

 the earlier stages are retained after the last molt (A. aspasia and A. xanthopus). This remains 

 to be verified. 



We had from a study of this genus (also of Khescyntis and Dysdaemonia) referred these 



moths to the subfamily Agliina?, the venation being similar to that of Aglia tau. And it is a 



matter of no little interest to find that the young freshly hatched larva is somewhat similar in 



armature to that European genus, whose nearest allies belong to the South American fauna, 



and also to Cercophana. 



ARSENURA XANTHOPUS (Walker). 



Rhescynlis xanthopus Walker, Cat. Lep. Het. Br. Mus., VI, p. 1327, 1855. 

 Rhescyntis xanthopus Kirby, Syn. Cat. Lep. Het., I, p. 769, 1892. 



LARVA. 

 Peters, Het.-Raupen, Taf. II, figs. 2, 2a, p. 9, 1898-1901. Pupa also figured. 



Imago. — 2 s . Antenna? more completely bipectinated, and the pectinations much longer 

 than in the other species examined by me; those of the distal pairs but little shorter and smaller 

 than those of the basal pair; the joints slender and pectinated to the tip of the antenna. Palpi 

 stout as usual. Head dark vandyke brown, with no pale band between and pale tufts at the 

 base of each antenna as occurs in A. armida. Maxilla? unusually well developed, very slender, 

 united, and making about two coils. Body stouter than in A. armida. 



Fore wings a little more rounded at the apex and less subfalcate than in A. armida; hind 

 wings not excavated behind the apex, as they are in A. armida. Markings quite different 

 from those of A. armida and pandora, though the ground color is the same fawn color with 

 Vandyke brown shades and lines. Basal line bent rectangularly and sending a point toward 

 the hinder end of the discal spot, and inclosing an oblong ash-fawn area, which also extends 

 beyond the basal line along the costa to the outer third of the costa, and incloses the large 

 distinct lunate discal spot, which is more distinct than in the other species examined by me. 

 Extradiscal line pale cream white, very deeply sinuous, the middle loop not divided into two 

 scallops in the middle of the wing as in A. armida and pandora; beyond are two series of fawn- 

 colored lunules with two linear whitish lines, and a submarginal row of Vandyke brown lunules 



1 Die Heteroceren-Raupen (und Puppen) des H. T. Petersschen manuskriptwerkes; Biologische Beitrage zur Brasilianischen Schmetterlings- 

 fauna, Neudamm (1898J-1901. 



