378 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



margin abruptly sinuated, margin of the siiias with a coUum, which 

 becomes narrower each side as it runs outward to the exterior angles, 

 behind each eye with two dragged indentations. Scutellum flattened 

 on the middle, remotely, a little coarsely, punctate, the apex and a lit- 

 tle before it somewhat rugulose. Legs pale chestnut-brown, or ferru- 

 ginous, the spines and teeth i3iceous, those of the outer edge of anterior 

 tibiae short and not very stout. Propleurae and outer area of the meso-, 

 meta-, and epi-sterna pale, saiooth, highly polished. Corium finely, re- 

 motely punctate, the punctures somewhat obsolete upon the disk, those of 

 the sutures coarser ; membrane white, longer than the venter. Venter 

 smooth, highly polished, faintly wrinkled on the sides of the disk and 

 pale, posteriorly. 



Length 5 millimeters. Width of base of pronotum 3 millimeters. 



This very interesting little species, which might easily be confounded 

 with either Macroporus repetitiis or Rhytidoporus indentatus, was first 

 discovered by Mr. Benjamin H. Smith in the vicinity of Denver City, 

 Colo. Since then it has been taken in Dallas County, Texas, by G. W. 

 Belfrage ; and a few specimens occurred to me while collecting insects 

 near the foot-hills of the Rocky Mountains, west of Denver, in August^ 

 1875. The summer was a particularly rainy one, and the sudden chill- 

 ing of the atmosphere by a hail-storm would cause this insect, together 

 with beetles, flies, Hymenoptera, and other Semipteni, to take refuge 

 under the tufts of grass and roots of Yuccas and other flowers and herbs, 

 where they remained secure from the driving elements. 



^THUS Stal, 



Oval, long oval, or subovate, moderately convex ; head short and 

 wide, the margins reflexed, the submargins with erect teeth and bristles ; 

 the lateral lobes flattened, equal to the tylus in length ; the base of the 

 head prominently convex; ocelli large, far apart, placed behind the 

 posterior line of the eyes. Rostrum of medium length, stout, the second 

 and third joints arcuately expanded, the basal joint not exceeding 

 the bucculte in length ; bucculse narrow and long ; antennae of five 

 joints, the joints moderately short, the second joint longer than the 

 third, the fourth and fifth long-ovate, subequal. Pronotum subquad- 

 rate, wider than long, the sides more or less obliquely narrowing ante- 

 riorly, remotely ciliated, the anterior margin deeply sinuated to receive 

 the head, destitute of a collum, or only having a thickened edge on 

 that part. Presternum raised, broadly grooved, the lateral flaps narrow 

 and short. Ostiolar canal flat, of medium length, set on an oblique and 

 acute scale. Anterior tibife but moderately expanded, the exterior mar- 

 gin with a few long spines ; posterior tibiae long and rather straight. 

 Scutellum triangular, longer than wide, narrow at tip, and contracted 

 just before the tip. Corium a little convex, of medium width, the costal 

 margin broadly curved, with the edge thickened before the middle, and 

 remotely ciliated ; the posterior margin obliquely truncated, with the 



