278 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



to that of the other species; the usual tooth on the edge of the costa, 

 near the end of the first posterior vein, is very little projecting. Length 



Eab.— Oregon (H. Edwards). A single specimen. This species is 

 very like P.Jlavvpes from the Atlantic States, but is smaller and differs 

 in the coloring of the abdomen. 



Lasia kletti Osten Sacken, in Lieutenant Wheeler's Report Ex- 

 plorations and Surveys, etc., vol. v, Zoology, 804. — Arizona. 



OCN^A HELLUO n. sp. — Two submargiual cells; five posterior cells, the 

 first divided in two by a cross- vein, and the second half of it closed and 

 petiolate, the fourth posterior cell likewise closed and short-petiolate ; 

 all the longitudinal veins reach the margin ; body black, beset with short 

 yellowish pile; hind margins of the abdominal segments with broad 

 yellow borders, expanding along the lateral margins; legs yellow, 

 including the coxse. Length 13-14'""'. 



The venation is like that of 0. calida (Wiedemann, Auss. Zw., ii, tab . 

 vii, f. 2&), with the following modifications : — 1. The third vein emits a 

 branch some distance beyond the cross-vein dividing the first posterior 

 cell; thus a second submarginal cell is formed; 2. The cross- vein in the 

 first posterior cell is just opposite the cross- vein at the base of the second 

 posterior cell, and not far beyond it, as in Wiedemann's figure ; 3. The 

 vein between the second and third posterior cells reaches the margin ; 

 4. The fourth posterior cell, which is closed, is much longer, forming an 

 irregular parallelogram, with a cross- vein at its base. 



Antennae dark-brown, basal joints reddish, the elongated third joint 

 also somewhat reddish on the inner side. Thorax black, shining, 

 clothed with dense and soft yellowish-gray pile, almost rendering it 

 opaque; humeral callosities whitish-yellow; an tealar callosities brownish. 

 Abdomen black, densely clothed with short, erect, yellow pile ; all the 

 segments with broad clay-yellow hind borders, expanding laterally so as 

 to occupy the whole lateral margin ; ventral segments black, with broad 

 clay-yellow hind borders. Legs including coxse yellow, the extreme end 

 of the last tarsal joint and the ungues black. Wings very slightly tinged 

 with brownish ; costal cell a little more saturate. 



Eab. — Dallas, Texas (Boll). One specimen. 



Observation. — This fine species is not unlike Erich son's figure of 0. 

 longicornis (Entomographien, tab. i, f. 8), but the venation is different, 

 the black on the abdomen occupies more space, the hind tibiae are 

 brown, the abdomen much stouter; the size is larger by one-half than 

 the hair-line of the figure. . 



Opsebius dilig-ens n. sp. — Of a slightly metallescent brownish- 

 black color, clothed with brownish-yellow pile ; legs brownish-yellow ; 

 wings tinged with brownish, the tip hyaline; first posterior cell divided 

 in two by a cross- vein ; the bases of the third and fourth cells nearly on 

 the same line; anal cell closed and petiolate. Length about S"^"". 



The venation is like that of the European 0. inflatus Loew (Wiener 



