84 NORTH AMERICAN 



twice as wide as the eye, equally trilobed by the very feeble sulcations ; 

 intermediate surface very acutely and strongly convex ; punctures small, 

 close, isolated, evenly distributed ; ocular lines meeting at less than one 

 length in advance ; antennae shorter than the width of head, rather robust, 

 black, club distinct ; third and fourth joints equal, fifth and sixth shorter, 

 equal, eighth but very slightly shorter and rather less robust than the 

 seventh, joints of club dark piceous-brown, increasing rapidly in length and 

 thickness, very sparsely pubescent ; maxillary palpi moderate, piceous-black, 

 first joint dark piceo-testaceous, third somewhat robust, compressed. Pro- 

 thorax very robust, arcuately and very rapidly widening to the middle, where 

 it is five-sixths as wide as the head, and distinctly wider than long ; sides 

 thence rather rapidly convergent and very feebly arcuate ; anterior and 

 posterior margins nearly equal in length and curvature ; surface very feebly 

 and obliquely tuberculate near the liasal angles, just perceptibly and trans- 

 versely impressed immediately behind the anterior margin ; very finely, 

 rather feebly, very closely, evenly, but somewhat confusedly punctate, inter- 

 spaces very indistinctly granulate. Elytra at base very slightly wider than 

 the head ; sides feebly divergent posteriorly, distinctly longer than the width 

 at base, and feebly arcuate ; together rather narrowly, roundly, and dis- 

 tinctly emarginate behind ; suture one-third as long again as the pronotum ; 

 surface rather depressed and even ; moderately coarsely-, xery closely, deeply, 

 and evenly punctate, interspaces narrow and highly polished, very feebly 

 reticulated. Abdominal segments decreasing rapidly and slightly arcuately 

 in -width, first as wide as the contiguous elytra ; surface broad, feebly convex ; 

 coarsely, very closely, and evenly punctulate, becoming much more finely so 

 toward the tip ; transverse carinae not cusped, finely and acutely dentate, 

 intervals evenly rounded. Legs short, slender, black above, dark piceous- 

 brown beneath ; first joint of posterior tarsi four-fifths as long again as the 

 second, equal in length to the fifth, second, third, and fourth joints uniformly 

 and gradually decreasing in length. Under surface of the abdomen polished, 

 black, rather sparsely and somewhat coarsely punctulate. 



Male. — Fifth ventral segment not perceptibly modified ; sixth sinuate at 

 the tip, sinus occupying nearly the entire segmental apex, evenly rounded, 

 and about eight times as wide as deep. 



Fi male. — Unknown. 



Length 1.9 mm. 



British Columbia, 2. 



The observation concerning the sexual modification of the sixtli 

 ventral segment is open to a little doubt, owing to the damaged con- 

 dition of the type specimen. 



65. S. atoiliarius n. sp. — Form slender. Pubescence almost completely 

 invisible, except toward the borders and tip of the abdomen, where it is 

 exceedingly short, setiform, sub-recumbent, cinereous, and rather sparse. 

 Head moderate, twice as wide as long ; interoeular surface not twice as wide 

 as the eye, flat ; equally trilobed by the very indistinct sulcations ; punctures 

 coarse, deep, very closely approximate, evenly distributed ; ocular lines 

 meeting at less than one length in advance ; antennae very slightly longe 



