CARSIA; CHESIAS. By L. B. Prout. 



179 



20. Geiius: Carsia Hhn. 



Only differs essentially from the typical form of AnuUis (costal vein of hindwing anastomosing in both 

 sexes) in having the foretiljia unarmed. In addition, the 2"'' median vein of the hindwing is more oblique 

 and consequently runs into the hindmargin nearer to the hinder angle. I only know one of the species but 

 both further agree in their small size and in their scheme of markings. 



Confined lo the Palearctic and Nearctic Regions, only two species known. 



C. perpetuata Led. Near paludata, agreeing in shape. Greyish-white. Forewing with antemedian perpetuata. 

 band etfaced in its anterior half, postmedian effaced in ils posterior part, their colour yellowish-brown; discal 

 dot very feeble; distal area washed with wood-brown; an oblique dark shade from apex; uiedian vein, fii-st 

 subcostal and the three radials marked with blackish longitudinal lines; fringe pale, dark-chequered. Hindwing 

 much more weakly marked. Forewing beneath grey-brow^n as far as the postmedian line, thence showing 

 Iraces of the upperside markings. Hindwing beneath rather darker and better marked than above. Transcaucasia. 



paludata. 



ohscurata. 



labra- 

 doriensis. 



C. paludata is widely distributed in high latitudes and is common to both hemispheres. It is divisilile 

 into three principal races. — paludata Thnh. (=: sororiata Hhi. = prainaria Ev.) (6g) is of a rather uniform 

 grey or bluish-grey colour, the lines of the forewing usually not, or scarcely, accompanied by dark bands 

 in the central area, the fine white line which follows the postmedian soldom sharply expressed, often almost 

 obsolete, except anteriorly; reddish shading entirely wanting or confined to the region of the oblique apical 

 streak. Under surface dark reddish grey. Inhabits Scandinavia, Arctic Russia and N. Siberia; also, according 

 to Staudinger, the Kentei Mountains. — ab. obscurata Schoi/en is much darker than the type-form, with the 

 reddish shade altogether obsolete; according to the figure, the dark bands are, however, better developed than 

 in typical paludata. Described, as a possible local race, from Sydvaranger. — labradoriensis Sommer (^ ? 

 boreata Pack.) is also poorly marked, but is narrower-winged, more brownish grey or tinged with reddish. 

 Only known from Labrador, but I have seen a similarly coloured example from E. Siberia and 1 suspect that 

 boreata Pack, (an older name), from Mount Washington (New Hampshire) is nearly or quite the same form. — 

 imbutata Hbn. (= sororiata Tr. nee Hbn) (6g) is much more variegated. Ground-colour more whitish, with imhittata. 

 subbasal line and two bands in the median area distinct, brown, distal area from about the S"" subcostal to 

 the 1 ^' median more or less strongly suffused with red-brown. Under surface lighter and more strongly reddish. 

 Extremely local in N. Germany, the Alps, Scotland, N. England and N. and Central Russia. — The egg is at 

 first whitish yellow, becoming deeper yellow; micropylar rosette 8-leaved; sides with irregular reticulation, in 

 places undeveloped. The winter is passed in this condition. The larva is rather stout, of uniform thickness, 

 dorsal surface rather deep brownish-red, with very fine blackish-red dorsal and subdorsal lines; a broad bright 

 yellow lateral stripe containing at the folds between the middle segments some beautiful red spots; venter 

 pale greenish yellow with paler, dark-edged central line. Feeds on Vaccinium in spring and early summer, 

 showing a preference for the flowers. Pupa slender, antemia-cases ending in a small bifid projection; yellow- 

 brovsTQ, abdomen more reddish. The moth frequents bogs and moors and flies at dusk but in hot weather is 

 restless by day. It is on the wing in July and August. 



21. Genus: Chesias Tr. 



Closely akin to Lithoste^e, perhaps scarcely separable on a strictly scientifically grounded system. Some 

 of the few distinctions given by Lederer are untenable and the chief difference lies in the more strongly glossy 

 wings, rounded apices and in the exceptional resting-posture, the wings being more closely rolled up than in 

 most Geometrids. The foretibia is perhaps less extremely thickened than in most Lithostege, but intergrades 

 occur in that genus; the inner claw is strongly developed, but the outer is slight and I can find no process 

 in the middle. The tongue, antenna and legs are less elongate than in Aiiattifi. The costal vein of the hind- 

 wing anastomoses with the cell in both sexes. 



The larvae ol the two be.st-known species feed on broom and are moderately elongate, smooth, pretty 

 uniformly cylindrical. The pupae are very distinct from those of AnaUis in the much shorter leg-cases, which 

 only project slightly, scarcely reaching as far as the end of the 5"^ abdominal segment, and are remarkable 

 for the presence of large circular, or somewhat oval dorsal depressions, one on each segment from the P' to 

 the 8"' abdominal. Unfortunately I -cannot compare LUhostege pupa. The duration of the pupal stage is irre- 

 gular, especially in rufata, and both the best-known species have also a peculiar habit on emergence, often 

 remaining for many hours before the expansion of the wings takes place. The same has been observed in 

 LUhostege griseata, which has even delayed as long as 36 hours before expanding. 



