no. i. BOMBYCINE MOTHS OF NORTH AMERICA— PACKARD. 29 



Vein III 2 is never detached so as to form an independent vein; there is only a tendency to it 

 in Nudaurelia, the tendency being most marked in [Acanihocampa] belina. The venation is 

 very uniform. The number of veins is invariably eight. 



Fore wings : The discal cell rather narrow; the two discal veins form a line wliich is situated 

 either in the middle (Usta, Salassa) or a little beyond the middle of the wing (Bunaea), and 

 the line varies in being curved or bent outward or inward. It is situated farthest outward in 

 Bunaea. 



Vein II, [III, in revised nomenclature] arises before the origin of the stalk of II 3 and U it 

 in the outer third of the discal cell (in Vsta, Cirina, Imbrasia, Antherina, Nudaurelia, Gynanisa, 

 Lobobunsea, and Salassa). The same vein in Thyella, [Acanihocampa] belina and Bunaea 

 arises at the end of the discal cell in front of the anterior discal vein. 



Hind wings: Vein III 2 semiindependent in Imbrasia and Antherina; in [Acanihocampa] 

 belina it becomes almost entirely independent, more so than in any other genus of the group. 



[The original definition of Bunaeinse, in the place sited, is as follows: 



"Antennae bipectinate, tip filiform, or pectinated to tip. Vein III 2 is never detached so as 

 to form an independent vein. Wings usually very large, and in the more specialized genera 

 closely approaching the Saturnian Anthersea (a case of parallelism or convergence), but the 

 larvae are entirely different, not spinning a dense cocoon and being armed with stout long spines 

 (in certain genera spinulated), instead of soft tubercles crowned with several small short spines. 

 Pupa like that of Eacles in type, ending in a large spine-like cremaster, and subterranean. 



There are three groups in this subfamily. The first and most generalized (Imbrasise) is 

 represented by the three genera of which Vsta is the most generalized; while Cirina, and 

 especially Imbrasia, with its tailed hind wings, is the most specialized. [Here also Gonimbrasia.] 



The second group is a more natural one, the Bunaese, all the three genera being closely 

 allied, and then - larva? known. They are Thyella, [Acanthocampa] belina and Bunaea. 



The third is perhaps more modern, more specialized, some of the forms, as Nudaurelia, 

 closely mimicking Antheraea of the Satumiidae, in the shape of the antennae, wings, and the 

 presence of large ocelli similar to those of the silk-spinning family, though the larvae are very 

 different as well as the transformations. 



USTA Wallengren. 



[Usta Wallengren, Wien. Ent. Mon., VII (1863), p. 142.] 

 [Type Usta wallengrenii (Felder).] 



Imago. — s. Head moderately wide in front; fairly prominent, scales long, erect, adding 

 to the size of the head and prominence of the front. Antennae of the male unipectinate, well 

 pectinated, nearly to the tip, the last five joints without pectinations; the joints numerous 

 (50), very short, only one pair of (basal) pectinations present with no vestiges of distal pairs 

 which are naked, scarcely ciliated. Palpi very stout, thick, and short, only reaching to the 

 front; consisting of but a single joint, small and short. Thorax moderately stout. No tongue 

 visible even after the removal of a palpus. 



Fore wings rather narrow and small, of nearly the same proportions as in Saturnia; costa 

 straight at base, much curved toward the apex, wliich is much rounded, unusually so; outer 

 edge not so long as the inner edge, straight, not incurved. Hind wings moderately wide; apex 

 weU rounded, outer edge not very convex; abdomen not quite reaching the inner angle of the 

 hind wings. 



Venation: Vein II, arises not far beyond the middle of the discal cell, and close to the 

 origin of the stalk giving rise to II 3 and II 4 . Vein II 2 present. Vein III 2 , not forming an inde- 

 pendent and giving rise to the anterior discal vein; the two discal veins directed inward, forming 

 a common line bent inward. Hind wings with the discal cell very long, the discal veins being 

 situated far beyond the middle of the wing, the two together being sharply bent inward, the dis- 

 tance between the origin of veins II and III being the same as between the origin of the latter 

 and of the posterior discal vein. 



