558 GEOLOGICAL SURVEY OF THE TEEEITOEIES. 



transverse black bands, and expanding three inches. It was " taken by 

 Mr, Nuttall near the Eocky Mountains " (Harris), and will doubtless 

 occur in Colorado. 



Semileuca Maia, Walk. — Several specimens from Denver City, Octo- 

 ber 4 (Lieutenant Carpenter). These specimens only (liffer from New- 

 England examples in the wider white band. I am inclined to regard 

 Mr. Stretch's H. Nevademis as a local variety of the present species, 

 since it differs apparently only in the " prothorax being pale-rusty.'' 

 In a 5 from Massachusetts, "the halo around the discal spot is separ- 

 ated from the basal patch," as in the Nevada form. It should be observed 

 that the width of the band varies greatly in the Massachusetts speci- 

 mens. In one 2 from Massachusetts, the white band on both wings is 

 nearly as wide as in any of the Colorado specimens. The patagia are also 

 whitish at base, thus approaching, though not very closely, Mr. Stretch's 

 figure of H. Hfevadensis. 



Telea Polyphemus, Hiibner. — The larva of this species was found on the 

 willow at Clear Creek by Lieutenant Carpenter. It spun a cocoon Sep- 

 tember 21. 



Cernra borealis, Boisd. — One rubbed, imperfect specimen occurred in 

 Montana, where it was obtained by Hay den's expedition in 1872. 



Euchcetes Egle, Harris. — An albino form occurred at Plum Creek, 

 June 29 (Lieutenant Carpenter). It differs from an albino of the same 

 species from Kansas (Mus. Bost. Soc. Nat. His., collected by W. H. 

 Dale) in the thorax being white. It apparently differs specifically from 

 Mr. Stretch's U. Oregonensis from Oregon. 



Arctia Blakei, Grote. — "Colorado, Eidings" (Grote). 



Arctia Quenselii, Paykull. — The occurrence of this species on the alpine 

 summits of Colorado is of great interest, as extending its wide geo- 

 graphical range. It occurs in the Alps at the height of about 8,000 

 feet, on the elevated portions of Lapland, in Labrador near the level of 

 the sea, and again on the summit of Mounts Washington and Madison 

 of the White Mountains of New Hampshire. The two Labrador indi- 

 viduals in the Museum of the Peabody Academy of Science at Salem are 

 the typical Quenselii ; the White-Mountain specimen, in the yellow fringe 

 of the tore- wing, and a Y-shaped white spot on the hind- wings, while 

 otherwise closely resembling the typical Labrador Quenselii, has a ten- 

 dency to resemble Moeschler's Arctia speciosa, which I would regard sim- 

 ply as a variety of Quenselii. A third variety, or race, is indicated by the 

 two Coloradian specimens, in which the veins are black 5 the wing is less 

 slashed with yellow, but the other markings are the same, both on the 

 wings and body. The two Coloradian species differ ; one in having the 

 hind-wings dark as in Quenselii, and the other with whitish wings 

 slashed at the base with black, and with two series of marginal dark 

 spots, somewhat as in var. speciosa ; in the latter individual, the mark- 

 ings on the fore-wings are broader and the two outer triangles formed 

 by the bands much smaller than in the other. 



The supposed larva of this species (Fig. 14, magnified twice) has been 

 discovered on Mount Washington by Mr. F. G. Sanborn, June 25, and 

 I have collected it on the 8th of July, at Square Island, Labrador, on 

 the larch. It is remarkably short, thick, and broad, a little flattened, 

 and so densely covered with short, evenly-cut hairs, with long, spread- 

 ing spinules, that the body cannot be seen. The dorsal hairs are short- 

 est and thickest 5 those on the sides are longer and more uneven. Seen 

 from above, both the head and tail are covered by overarching hairs, 

 both ends thus appearing alike. Head black, body beneath black 5 

 abdominal legs livid. Hairs dark-brown, appearing as if dusted over, 



