72 GEO. H. HORN, M. D. 



A, desertus Horn. — Obloug oval, slightly broader bebiiul, moderately con- 

 vex, rufoferrugmous or pale brown, moderately shining. Head moderately con- 

 vex, not closely punctate, anteriorly granulate and rugose. Clypeus broadly, but 

 feebly emarginate, angulate each side and with a small erect denticle, sides ar- 

 cuate with a feeble sinuation posteriorly, gente feebly prominent, obtuse. Thorax 

 twice as wide as long, not narrowed in front, sides feebly arcuate, hind angles 

 very obtuse, base arcuate with a deep marginal line, disc moderately convex, 

 with coarse and moderately deep punctures very iri-egularly scattered with a few 

 finer punctures intermixed, a space near the side comparatively smooth, a few 

 conspicuously large punctures near the front angles. Elytra as wide at base as 

 the thorax, humeri finely dentate, sides slightly arcuate, disc deeply striate, cre- 

 nate-puuctate, intervals convex, smooth, crenate on the inner side. Mesoster- 

 num opaque, finely rugulose, cariuate between the cox?e. Metasteruum smooth. 

 Abdomen very sparsely punctulate. Anterior tibiae tridentate externally, obso- 

 letely crenate above. Posterior femora sparsely finely punctulate, a short mar- 

 ginal line near the knee ; posterior tibise without accessory spinule, the first tarsal 

 joint shorter than the long spur. Length .12-. 18 inch ; 3-4.5 mm. 



Among the species with dentate clypeus the present is readily 

 known by its color and the very irregular coarse punctuation of the 

 thorax. One other species of the group has the latter character but 

 this has a distinct accessoiy tibial spinule. The venti'al segments 

 have the crenation along the anterior margin as is usual in the genus. 



Occurs in California, near Fort Yuma ; in Arizona ; also in southern 

 Utah. 



Ao ab<litiis Hald. — Form slender, elongate, parallel, subdepressed, piceous, 

 moderately shining, legs pale reddish brown. Antennae, and palpi rufotestaceons. 

 Head moderately densely punctured posteriorly, smoother at middle, roughly 

 punctured or subgranulate in front. Clypeus broadly, but feebly emarginate, a 

 distinct angulation or small denticle each side, the sides arcuate, genae moderately 

 prominent obtuse. Thorax not quite twice as wide as long, slightly narrower 

 posteriorly, the sides feebly arcuate, the hind angles rounded, base arcuate, the 

 marginal line well marked, disc moderately convex, a slight depression at the 

 anterior angles, the punctures moderate in size, closely placed, a little finer in 

 front, dense toward the sides, especially in the front angles. Elytra as wide as 

 the thorax, humeri dentate, sides nearly parallel, moderately deeply striate, 

 striae rather coarsely crenate-jtunctate, intervals moderately convex, with a series 

 of finer punctures on the outer side of each ventral. Mesosternura opaque, stri- 

 gose punctate in front, carinate between the coxae. Metasteruum coarsely sparsely 

 punctate at middle, more rugose and finely at the sides. Abdomen coarsely punc- 

 tate, spai"sely at middle, more elevated at the side. Anterior tibiae tridentate 

 externally and feebly crenate above. Posterior femora sparsely punctate or 

 nearly smooth, with at most a feeble trace of a marginal line near the knee: 

 posterior tibia without accessory spinule, the first tarsal joint not longer than the 

 long spur. Length .14-.16 inch ; 3.5-4 mm. 



This species seems widely distributed on the American Continent, 

 specimens from Columbia, S. A., having been described by Harold 



