86 MEMOIRS NATIONAL ACADEMY OF SCIENCES. vol. xii, 



The sides of the body are black brown, beneath (including the abdomen) rather bright 

 reddish brown; abdomen above dark brown, with five ochreous bands; the end snuff-yellow 

 ochreous. 



Expanse of fore wings, o" 88 mm. ; 9 104 mm. 

 Length of fore wing, <? 42 mm. ; 9 49 mm. 

 Breadth of fore wing, <$ 25 mm.; 9 27 mm. 

 Length of hind wing, s 35 mm. ; $ 40 mm. 

 Breadth of hind wing, o* 28 mm.; 9 26 mm. 

 This fine large species has much broader wings than in the other species, those of the hinder 

 pair extending farther beyond the end of the abdomen, while the lines are white, broken up 

 into venular spots, and the general color is ruddy chestnut brown instead of roseate. 

 Geographical distribution. — Jalapa, Mexico (Barrett). 



DIRPHIA SPECIOSA (Cramer). 



Plate LIU, fig. 2. 



[Attacus speciosa Cramer, Pap. Exot., II (1779?), PI. 107, B.] 



Dirphia speciosa Walker, Cat. Lep. Het. Brit. Mus., VI (1855), p. 1363. — Druce, Biol. Centr. Amer., Lep. Het., I 



(1886), p. 195.] 

 [Plateia speciosa Kirby, Cat. Lep. Het., I, p. 791.] 



Imago. — One 9 • Head and thorax dull snuff -yellow ochre; wings of both pairs of a uni- 

 form delicate rose-pink, with traces of a diffuse brown extradiscal line, and a white diffuse 

 linear discal mark, which on the under side is very indistinct. Cramer figures it with a dis- 

 tinct >- mark, the stalk of the >- extending out along the extradiscal space. Beneath there 

 are no Lines or other markings. Palpi not reaching the front, not very stout, depressed. Fore 

 wings rather produced toward the apex and hind wings well rounded on the apex. Abdomen 

 black-brown, with five white rings on the front edge of five segments; end of the abdomen 

 snuff-yellow. The thorax is partly denuded [of hairs], but there are no traces of erect stiff 

 flattened ones. 



Expanse of the fore wings, <? 88 mm. 



Length of a fore wing, <? 45 mm. 



Breadth of a fore wing, 6" 22 mm. 



Length of hind wing, o* 32 mm. 



Breadth of hind wing, o* 21 mm. 

 This is a larger species than J), semirosea, with longer fore wings, which are more pointed 

 at the apex, while the hind wings are longer. 



My single specimen (a duplicate from the British Museum, and named from the British 

 Museum collection) is rubbed and battered. By its antennal structure, the presence of vestiges 

 of distal pectinations, which do not occur in the two other species, I infer that this is probably 

 one of, if not the most, primitive species of the genus. 



Geographical distribution. — Ega, Demarara (British Museum); Surinam (Cramer). 



DIRPHIA SOMNICULOSA (Cramer). 



[Bombyx somniculosa Cramer, Pap. Exct., II (1779), pi. 100, A. B.] 

 [According to Kirby, this is the type of Plateia Hubner.] 



A large reddish brown species, in shape like D. speciosa, but with no discal mark. Fore 

 wings crossed by five whitish broad shades. Abdomen banded with red and ocher. See 

 W[alker]'s description [Cat. Lep. Het. Brit. Mus., VI, p. 1360]. 



[HYPERDIRPHIA Packard.] 



[Hyperdirphia Packard, Journ. N. Y. Ent. Soc, XI (1903), p. 245, was based on Attacus 

 tarquinia Cramer, described from Surinam. According to Kirby, tarquinia is the type of Dirphia. 

 In Dr. Packard's MSS. I find tarquinia still in Dirphia, with no reference to Hyperdirphia, but 

 the account was evidently written prior to the publication of Hyperdirphia. The diagnosis 

 of the latter genus was as follows :] 



