186 



OTOPLECTA: TRICHOPTERIGIA. By L. B. Prout. 



28. Genus: Otoplecta W 



arr. 



frigida. 



Characters intermediate between those of Mysticoptera and Trichopterigia, shape nearer to the former. 

 Palpus long, rough-scaled. Antenna simple. Hindtibia with terminal spurs only. Forewing with areole single. 

 Hindwing relatively larger than in most of the group; costal in both sexes anastomosing with cell; 2"** subcostal 

 in cf separate, in ? shortly stalked; discocellulars biangulate; d" with submedian vein wantiug, inner margin 

 folded over from base to beyond middle, covering a pocked which opens to the upper surface. 



This genus was established by Warren for the present species, which is only known from Japan and 

 shows no very close affinity with any other. Perhaps the earlier stages, which are at present unknown, will 

 show whether it really belongs to the Lobophora group or whether — as the coloration would suggest — it is 

 a much modified development of Eulype. 



0. frigida Btlr. (J3b). Glossy white with black markings. Forewing with basal patch rather broad but 

 mixed with white; median area also broad, broken into two bands which nearly meet at the costa; its proximal 

 edge strongly curved, its distal projecting slightly about the 1^' radial and acutely behind the 3''' radial; the 

 white band which follows uniform in breadth throughout, containing a row of black dots; distal area almost 

 entirely black, a very fine white subterminal line indistinct or nearly obsolete, but nearly always distinct at 

 costal margin; fringe black, more or less white-spotted. Hindwing grey, with a white band not far from the 

 distal margin, the area beyond it blacker, more or less intersected with white between the veins; a moderate 

 black cell-dnt. Underside similar, forewing less varied proximally. Japan, apparently common at Yokokama. 



29. Geuus: Trichopterigia Hmpsii. 



Palpus with 2"'^ joint moderate or (especially in the ?) long, shortly rough scaled. Antenna simple. 

 Hindtibia whh terminal spurs only. Forewing with areole single, broad. Hindwing in cf with small lobe, 

 submedian vein wanting; in both sexes with discocellulars strongly biangulate, costal anastomosing with cell 

 (except only in volitans, which is doubtfully congeneric), 2"'' subcostal well stalked with P' radial. 



A development — chiefly Indian — from Nothopterijx or an allied form, differing in the single areole, 

 usually also in the longer palpus and the neuration of the hindwing. Entirely wanting in Europe, but a few 

 species reach the Eastern Palearctic Region. 



Early stages unknown. 



vulitam. T. volitans Bth: (= expressata CAr.) (8 a) is aberrant in the non-anastomosis of the costal vein of the 



hindwing in the cf, the scaling is rather denser than in most Trichopterigia and the facies more nearly that 

 of a Nothopiteryx. Ground-colour white, the forewing more or less heavily dusted with brown atoms but often 

 with a broad, almost clear space remaining proximally to the median band and a second occupying the distal 

 area from the 3''<^ radial to tlie hinder angle; basal area tinged with green, a fuscous subbasal line distinct; 

 the succeeding area more or less clouded with fuscous; central area of moderate breadth or rather narrow, 

 proximally with two strongly curved, closely approximated fuscous lines, filled-in with greenish, distally with 

 two less approximated ones, the outer strongly lunulate-dentate, the space between them again filled-in with 

 greenish, crossed by dark vein-marks; the area between these pairs of lines is very variable, almost entirely 

 dark-fuscous or clouded with that colour or whitish, merely fuscous on the veins; apical area with the 

 beginnings of some lines on the costa, then some greenish clouding, than a dark cloud between the radials; 



elegans. cell-dot fuscous. Hindwing whitish, usually with 2 or 3 faint grey postmedian lines. — ab. elegans Butl. has 

 the fuscous lines and vein-marks of the median area thickened, so as largely to supplant the greenish shade, 

 while the central part of this area remains white, crossed by thick fuscous lines on the veins. Yokohama. — 

 volitans inhabits Japan and East Siberia; Christoph found it in numbers at Nikolsk in the first half of April, 

 sitting on the tree-trunks in oak woods. 



consobri- T. consobrinaria Leech bears some slight resemblance to Acasis viretata, a small form of which we 



nana, have in error figured under this name, consobrinaria however, irrespective of the structural differences, has 

 the forewing of a paler and less bright green, the median area divided into two bands nearly as in Nothopterijx 

 grisearia or well-marked forms of carpinata, its boundary lines (especially the proximal) much less jagged than 

 in viretata, the markings in the distal area different and the hindwing white. Size of the preceding, forewing 

 with distal margin less oblique, proximal and distal areas pale delicate greenish, centre of median area whiter; 

 antemedian and postmedian bands crossed by dark vein-dashes. Hindwing white with the veins, a curved 



