SEMASIA. 57 



than its length beyond it : antennae with the basal joint thickened. Fore wings milk-white; 

 the cilia bright chestnut-brown^ with an inconspicuous oblique pale olive-grey fascia from 

 near the base to the middle of the dorsal margin; another of the same colour from the 

 middle of the costa, joining a bright chestnut-brown streak which divides the subobsolete 

 ocellated spot above the anal angle ; this streak contains two or three black scales and some 

 few sublustrous silvery- white ones : underside glossy pale chestnut, the costa narrowly white. 

 The hind wings pale grey, faintly shaded with chestnut, especially along the margins ; vein 4 

 of the hind wings is absent. Type c^" . Expanse of wings 22 millims. 



A single larva, found July 29th, 1871, near Mount Shasta, California, drawing together 

 the leaves of leading shoots of a species of Artemisia, produced a male in the following month. 

 The species is allied to the European S. pupillana, L. 



Semasia scalana. (Plate LXXIII, fig. 4.) 



Head cinereous grey ; palpi cinereous grey above, white at the base beneath, thickly 

 clothed, extending nearly twice the length of the head beyond it : antennae fuscous above, 

 paler beneath. Fore wings — oblong, three times as long as wide, the costa arched towards 

 the base; apical margin oblique, not perceptibly indented — reddish chocolate-brown; a few 

 scattered whitish scales at the base ; an oblique white, rather shining fascia from before the 

 middle of the costa to beyond the middle of the dorsal margin, divided by a narrow pale yel- 

 lowish-buff line ; some shining silvery streaks from the costa beyond the middle, divided by 

 pale yellowish fawn-colour, and extending to the ocellated spot, which is irrorated with 

 fuscous in its upper half, and contains in its lower half a patch of twelve (sometimes 

 sixteen) square black dots, divided into two groups of six or eight each by a lustrous steel- 

 blue streak, and margined on both sides by lustrous steel-blue : cilia whitish, irrorated 

 with fuscous. Hind wings brownish grey; vein 4 absent. 4 c?.- Expanse of wings 

 16 millims. 



June 1872, on the borders of California and Oregon. 



Semasia columbiana. (Plate LXXIII. fig. 5.) 



Head, thorax, and palpi speckled grey, the latter paler beneath, projecting about the 

 length of the head beyond it : antennae simple. Fore wings whitish, thickly irrorated with 

 greyish fuscous ; in the male three times as long as wide ; costa very slightly bulged near the 

 base ; apical margin scarcely sinuated ; dorsal margin convex towards the base ; a basal patch, 

 occupying the first third of the wing, sometimes greyish fuscous, sometimes buflP-brown, and 

 sometimes pale brownish buflp, margined with fuscous ; an oblique fascia of a corresponding 

 colour, sinuated on its inner edge, near the dorsal margin, sometimes with a branch towards 

 the costa before the apex ; a few sublustrous whitish streaks in the apical portion of the wmg. 



