1860 REPORT OF THE CHIEF OF ENGINEERS. 



his own words, u a Zyga?nid genus allied to Ctenucha and presenting some 'analogies in 

 the n eviration to Eudryas." 



Another closely allied variety was described by Walker in Cat. Het. B. M. iii, p. 

 626, vinder the name of Nemeophila Petrosa, he not having made the mistake, however, 

 of placing it in a new genus. 



Genus ARCTIA Schr. 

 Arctia Cervinoides. 



Arctia Cervinoides STRJSCKER, Proceedings Academy of Natural Sciences of Philadelphia, p. 

 151 (1876). 



One example, July 15, Upper Rio Blanco, differs from the type in having the second- 

 aries more blackish, and in the white lines of primaries being narrower in part. 



This was described from a unique example received from Colorado in 1875. It is 

 nearer to Qtienselii Payk. and Cervini Fall, than to any other known species. I know 

 of no other examples 'in collections besides the type and the one above alluded to. 



Arctia F-pallida, n. sp. 



Male expands 1 inch. Head above pinkish, beneath black ; thorax above pinkish, 

 with three black stripes, beneath black ; abdomen crimson above, with a black dorsal 

 stripe; below black; antennae black. 



Wings, upper surface primaries black, with a large pale flesh-colored mark resem- 

 bling the letter F ; this is formed by a mark extending from base of wing some dis- 

 tance from and parallel with the inner margin, to nearly two-thirds the length of 

 the wing ; from its outer extremity to the costa extends a somewhat bent line of 

 same color and width. Another such line also extends from the first mentioned to 

 costa, about midway between the last -mentioned line and base of wing, these three 

 lines thus forming a very conspicuous and distinct letter F. Secondaries scarlet, with 

 broad blackish margin ; a not very conspicuous dark mark extends from base to oviter 

 margin about one-third in from abdominal margin ; a blackish sp.ot connects with the 

 dark border of costa about one-third the distance from the apex ; fringe of abdominal 

 margin scarlet ; all other fringe of all wings dark grayish. 



Oue example of this handsome little species captured at the Rio Navajo July 13 ; it 

 belongs in same group with Nais Dru., &c. 



Genus SPILOSOMA Stph. 

 Spilosoma Antigone, n. sp. 



Female expands 1| inches. Head and body entirely pure shining white ; antenna? 

 white above, black beneath ; legs white, except the coxa? and femora of anterior pair, 

 which are yellow. 



All wings same pure shining white as the body ; primaries above, with an irregular 

 submarginal row of faint broAvnish dots ; the three or fouf toward the apex are ones 

 that are noticeable without close inspection ; another brown point at the intersection 

 of the median nervule with its two middle branches, this spot or dot is also very 

 faintly visible on the other surface, as is also a discal point on under surface of sec- 

 ondaries. 



One female, July 16, main Rio Blanco ; one female previously from Georgia. 



There are, besides this, four described species of SiJtlosoma, in -North America, 

 viz, Virginica Fab., CongruaVflk.., Vestal is Pack., and Latipennis, Stretch. From the 

 first of these the present species differs in its immaculate abdomen ; from the second, 

 in the absence of black bands on the tarsi and of the "four oblique, very imperfect, 

 and irregular bands composed of pale brown dots " ; and from the third and fourth in 

 the anterior coxa? and femora being yellow instead of rose-colored or pink. I thought 

 at first it might be Walker's Congrua, as the number of pale dots on primaries is not 

 necessarily specific in this and allied genera (as can be seen by the endless varieties 

 of Hyphantria Cunea Dru.), but the absence of black bands on the" tarsi and other points 

 stated by Walker have satisfied me of its distinctness. 



Genus HEMILEUCA W r lk. 

 Hemilettca Juno. 



Hemileuca Juno. PACKARD, Annual Report of the Peabody Academy of Science for 1871. p. 

 87 (1872). 



Three male examples, at Rio Florida, much worn. Packard says in his description 

 of this species that it is " similar in its form to H. maia." The present examples do not 

 agree with his description in this respect, as the wings are narrower than maia, are more 

 prolonged apically, are less rounded on exterior margins, and the primaries are much 

 hollowed in on costa. Packard says, "wings uniformly dark -brown." This conveys 

 an erroneous impression of the color, which is the same, only more dense and opaque, 

 as in the darker examples of maia, a sort of crape-like or semi-diaphanous black. He 



