1864.] ' 191 



almost reaching the postscutellum ; the elevated lines and central area 

 obsolete. Wings hyaline, with a faint yellowish gloss ; nervures fuscous 

 pale testaceous at base, stigma pale brown ; areolet 5-angular. Legs : 

 the two antei'ior pairs yellowish-fulvous ; the anterior coxai, the inter- 

 mediate pair above and a double line on the posterior pair behind, 

 whitish ; the middle coxas beneath, the posterior coxae, their femora, 

 except extreme base, and the apical third of their tibiae, black ; the 

 four anterior tibiae, the basal two-thirds of the posterior pair, and all 

 the tarsi, pale yellowish. Abdomen elongate, subeylindrical, very slen- 

 der at base, polished ; basal segment with a small tubercle on each side 

 before the apical third ; basal two-thirds of the first segment and the 

 basal half of the two following segments, black ; apex of the first and 

 apical half of the 2nd segments, pale fulvous ; remaining segments dull 

 rufo-fulvous. Length 5 lines; expanse of wings 9? lines. 

 Hab. — Maryland. E. T. Cressou. 



At first sight this species closely resembles Isch. vinmdus, but the 

 markings of the head and thorax are diiferently arranged. They are 

 certainly distinct. 



8. Isch. W-album, n. sp. 



Black; antennse with a yellowish anuulation ; face, orbits, lateral margins 

 of mesothorax and a spot on its disk, large spot on each side of pleura beneath, 

 seutellum, W on metathorax and the coxoe, yellowish-white; abdomen, except 

 1st segment, aud the femora pale fulvous ; wings hyaline. 



Male. — Head black ; face, orbits, broad on the cheeks, clypeus, man- 

 dibles and palpi, yellowish-white ; antennae more than half the length 

 of the body, porrect, black above, pale brown beneath, the 17th to 24th 

 joints, and the basal joint beneath yellowish. Thorax black, shining, 

 feebly punctured, the mesothorax impressed on each side in front ; the 

 collar above, a quadrate spot on the disk of the mesothorax, tegulae, a 

 sutural line before and a line beneath the fore wings, a large spot on 

 each side of the pleura beneath, an oblique line on each side above the 

 anterior coxre and also a spot in front, a spot beneath each hind wing 

 and another large transverse one behind, all yellowish-white; seutellum 

 rather convex, polished, entirely pale yellow, as well as a transverse 

 spot behind it; metathorax rather densely punctured, black, with a 

 large, more or less distinct, W-shaped. yellowish-white mark, the ele- 

 vated lines not well defined, the central area small and transverse. 



