OSTEN SACKEN ON WESTERN DIPTERA. 237 



attentively, that joint shows, on its incrassate, basal part, a more or 

 less distinct transverse suture, which also exists in Anthrax, and may in- 

 dicate that the third joint is very much shortened here and coalescent 

 with the style, their suture being very near the base of the joint. The 

 joint is onion-shaped at the base, with a slender, gently tapering, almost 

 linear, prolongation, ending in a point. I do not see any bristle at the 

 end. The body is more slender than in Exoprosopa* and the hairy cov- 

 ering of a more uniform color. 



Anthrax paradoxa Jaennicke (Exot. Dipt., 31, tab. ii, 16) probably 

 belongs here. The course of the second vein is the same in that species ; 

 only the cross-vein in D. serpentina is inserted in the middle of the sinus, 

 and not at its base. In the specimen from Georgia, to be mentioned 

 below, the cross- vein is placed very nearly as it is in Jaennicke's figure. 



Diplocampta Schiner (ISTovara, 119, tab. ii, f. 9) from Chili resembles 

 JDipalta in the curvature of the second vein ; nevertheless, it is evidently 

 different j the abdomen is not longer than the thorax, and narrower, 

 being gradually attenuated posteriorly ; the structure of the antenna is 

 different; the species is small (1J to 2 lines long), with nearly hyaline 

 wings ; the position of the cross-vein between the second and third veins 

 I is different. 



Dipalta, in Greek, means twice bent. 



1. Dipalta serpentina n. sp., 8 ? .—Body black, densely and rather 

 uniformly clothed with a short, appressed, pale yellow tomentum ; longer 

 pile on the pleurae and on the anterior margin of the thorax. Wings 

 subhyaline, with a pale brownish-yellow tinge, the base and two irregu- 

 lar cross-bands brown. These cross-bands are formed by the confluence 

 of large, round, brown spots on the cross-veins and bifurcations; the 

 first cross-band has a hyaline spot anteriorly in the proximal half of the 

 marginal cell ; posteriorly it is attenuated ; the second cross-band con- 

 tains a hyaline spot at its posterior end in the first and second, posterior 

 j cells ; the apex of the wing is hyaline, the end of the second vein clouded 

 (with brown; a much smaller cloud on the third vein ; a stump of a vein 

 'projects into the marginal cell a short distance before the cross- vein ; be- 

 jyond the cross- vein, the second vein is very deeply bisinuate. Legs 

 (densely clothed with fulvous scales, except on the tarsi, which are black. 

 Antennae, first two joints very short, reddish, sometimes darker; third 

 i joint black. Halteres yellow, slightly brownish at the base of the knob. 

 Proboscis not projecting beyond the oral border. Length 10-ll mm . 



Eab.— Mount Shasta district, California (H.Edwards); Clear Creek 

 Canon (Uhler); Colorado Mountains (W. L. Carpenter). Three speci- 

 mens. 



Observation. — I have a specimen from Georgia (EL K. Morrison) which 

 probably belongs here. The hairy covering of the body is of a very 

 saturate fulvous; the markings of the wings are of a darker brown; 

 the different position of the cross vein has been alluded to above. 



