48 NORTH AMERICAN 



larly incised at apex, triangle equilateral, slightly more than one-third as 

 wide as the segment. 



Female. — Sixth segment narrowly produced and bilobed at the apex, cusp 

 small, distinct, very feebly rounded, arms narrowly divergent and rather 

 acutely rounded. 



Length % 3.5, ? 4.2 mm. 



Alamosa, Colorado, 2. 



Easily recognized by its very rough, lustreless surface, and very 

 distinct sexual characters. 



29. S. aiiastomozailS n. sp. (Crotch MS.). — Form very moderately 

 robust. Pubescence short, rather close, coarse, semi-erect, cinereous. Head 

 rather small, more than twice as wide as long ; interocular surface nearly 

 flat, two and one-half times as wide as the eye ; longitudinal elevation 

 slightly narrower than the lateral portions, strongly and evenly convex ; 

 sulfations somewhat deep and prominent ; punctures coarse, rounded, 

 moderately close, evenly distributed, and deeply impressed, interspaces one- 

 half as wide as the punctures, feebly convex, and shining ; ocular lines 

 meeting at one length in advance ; antennae as long as the width of head, 

 rather slender, club large, basal joint black, remainder dark piceous-brown ; 

 third joint one-half as long again as the fourth, fourth slightly longer than 

 the fifth, sixth slightly longer and much less robust than the seventh, eighth 

 very robust, as wide as or slightly wider than the seventh, tenth joint slightly 

 the widest ; maxillary palpi long and slender, dark piceous-brown, becoming 

 pale piceo-testaceous at the base, fourth joint very distinct. Prothorax 

 almost uniformly and gradually increasing in width to the middle, where it 

 is four-fifths as wide as the head, and distinctly narrower than long ; sides 

 thence moderately convergent posteriorly and very feebly sinuate ; anterior 

 and posterior margins equal in length, the former distinctly the more arcuate ; 

 surface finely tuberculate along the sides near the canaliculation, and more 

 particularly near the basal angles ; rather finely, deeply, extremely closely, 

 and somewhat confusedly punctured, interspaces acute ; canaliculation short, 

 moderately deep, ami narrow, commencing just before the middle, one-fourth 

 as long as the pronotum. Elytra at base as wide as or just perceptibly 

 wider than the head ; sides very feebly divergent posteriorly, slightly longer 

 than the width at base, rather strongly and evenly arcuate ; together nar- 

 rowly and very strongly emarginate behind ; suture nearly one-third as long 

 again as the pronotum ; surface very feebly and broadly impressed on the 

 suture at and near the base, somewhat coarsely, very deeply, extremely 

 closely punctate and channeled, interspaces acute. Abdominal segments 

 decreasing uniformly and rapidly in width, first distinctly narrower than 

 the contiguous elytra ; surface rather strongly convex, extremely coarsely 

 and closely, sub-variolately punctulate ; punctures rounded and not coales- 

 cent, much finer and more distant behind ; transverse carinae tricuspid, 

 cusps very long, stout, aciculate at tips, prominent, lateral slightly shorter 

 than the middle ones. Legs rather long and slender, femora black, tibiae 

 and tarsi piceous-black beneath ; first joint of posterior tarsi three-fourths as 



