80 NORTH AMERICAN 



the last, longer than the next two together, fourth joint narrow, very oblique 

 and thin. 



Mule. — Posterior edge of the fifth ventral segment very feebly emarginate 

 in its middle sixth, emargination evenly rounded and scarcely measurable, 

 edge of emargination granulose ; sixth segment sinuate at apex, sinus nar- 

 rower than the apices and more acutely rounded, evenly rounded at the 

 bottom, one-half wider than deep ; seventh very feebly emarginate at apex. 



/■) mule. — Unknown. 



Length 3.0 mm. 



California, 1. 



This very distinct species differs markedly from costalis in the 

 structure of the head, and the nature of the punctuation of. the inter- 

 ocular surface, which is very much coarser than in that species ; there 

 are also many other minor differences. 



01. S. adelops n. sp.- — Form robust. Pubescence very short, fine, 

 somewhat close, evenly distributed, sub-recumbent, pioeo-plumbeous, not 



conspicuous; on the under surface of the abdomen it is more plentiful, 

 short, and cinereous. Head very small, twice as wide as long; interoeular 

 surface flat, three times as wide as the eye, equally trilobed by the rounded, 

 rather deep, and conspicuous sulcations ; punctures wry small, round, very 

 close, and evenly distributed : ocular lines meeting at more than two lengths 

 in advance ; antennae rather short, black, slightly longer than the width of 

 head, very robust, club prominent ; third joint one-fourth longer than the 

 fourth, fourth and fifth equal, sixth and seventh abruptly much shorter, 

 equal in length, the latter slightly thicker, eighth slightly elongated, thicker 

 than the seventh, nearly evenly elliptical, club rather compact, joints in- 

 creasing rapidly in length, tenth wider than long and broadest, last as long 

 as the eighth and ninth together : maxillary palpi intense black throughout, 

 rather short and robust, third joint densely clothed with cinereous pubes- 

 cence. Prothorax widest in the middle, where it is nearly seven-eighths as 

 wide as the head, and slightly narrower than long; sides thence extremely 

 feebly convergent posteriorly and nearly straight ; anterior margin shorter 

 and much more arcuate than the posterior : surface rather strongly tubercu- 

 late along the sides and above, and also along the margins of the canalicu- 

 lation : transversely and rather strongly impressed just behind the apex : 

 punctures very tine, closely crowded, and rather obscure ; between the 

 tuberculiform costae and in the canaliculation the punctures are more dis- 

 tant, with the interspaces very feebly lustrous, elsewhere nearly opaque : 

 canaliculation narrow, fusiform, two-thirds as long as the pronotum, termi- 

 nating at equal distances from the base and apex, rather deeply impressed. 

 Elytra at base one-third wider than the head ; sides just perceptibly diver- 

 gent posteriorly, longer than the width at base, very feebly and nearly evenly 

 arcuate; together feebly emarginate behind; suture one-half longer than 

 the pronotum; surface nearly as in costalis, though rather more feebly sculp- 

 tured. Abdominal segments uniformly and very rapidly decreasing in width, 

 first just visibly narrower than the contiguous elytra ; surface feebly convex, 

 rather finely, feebly, and closely punctulate ; transverse carinae tricuspid, 



