COLEOPTERA. 17 



together, club well developed ; third joint a little more than one-half as long 

 again as the fourth, fourth and fifth nearly equal, eighth notably shorter 

 than the seventh ; joints of club nearly equal, moderately elongated. Pro- 

 thorax equal in length to twice the head, widest at mid-section where it is 

 slightly narrower than the head ; sides from this point moderately convergent 

 posteriorly and slightly sinuate; surface densely punctate ; commencing at 

 the middle and extending for one-fourth the length there is a narrow, deep, 

 canalicular excavation, which gradually disappears posteriorly. Elytra at 

 base as wide as the head, together deeply emarginate anteriorly, and each 

 bisinuate posteriorly; sides slightly divergent posteriorly; humeral and 

 apical angles rounded ; length of suture perceptibly greater than that of 

 pronotum, and equal to the posterior width of elytra together ; surface 

 densely punctate, each elytron slightly swollen in the middle at the base, 

 these elevations gradually disappearing posteriorly ; a large reniform, orange- 

 yellow spot occupies the middle posterior fourth of each elytron, commencing 

 at a distance from the suture nearly equal to one-half its width. Abdominal 

 segments decreasing but very slightly in width posteriorly ; border very 

 prominent ; dorsal carinae very slightly sinuate posteriorly, acutely tri- 

 cuspid. Legs long and slender ; femora very pale testaceous, with a broad 

 band of pale fuscous near the tips ; tibiae very slender and slightly darker 

 than the femora ; tarsi very slender, posterior equal in length to three-fourths 

 the tibiae, first and second joints with a touch of fuscous at the tips, fifth 

 joint almost entirely pale fuscous ; first joint equal in length to the next 

 three together. First joint of maxillary palpi dark fuscous, second and 

 third pale yellowish-testaceous. Entire under surface of body piceous-black. 



Male. — Posterior edge of fifth ventral segment moderately emarginate in 

 its middle third, with the surface bordering on the emargination slightly 

 impressed; sixth segment triangularly incised in its middle half, notch three 

 times as broad as deep, with its anterior angle slightly rounded ; seventh 

 segment broadly emarginate at apex. 



Fondle. — Sixth segment broadly and evenly rounded behind. 



Length 3.9-5.0 mm. 



Columbus, Texas, 5; Arizona, 21. 



A tine species ; the orange spot is often very brilliant. 



5. S. semicolon Lee. — Form rather slender. Pubescence of entire body 

 very short and sparse, fiavo-cinereous in color. Head moderate, scarcely 

 twice as wide as long ; interocular surface well depressed, three times as 

 wide as the eye, deeply and closely punctured ; longitudinal elevation well 

 marked; ocular lines meeting at about two lengths in advance; antennae 

 slender, but little longer than width of head, uniformly deep fuscous, club 

 distinct ; third joint one-half as long again as fourth, eighth scarcely more 

 than one-half as long as the seventh, eleventh longer than the. tenth, joints of 

 club slightly elongated ; maxillary palpi testaceous, second joint rather paler 

 at base. Prothorax widest at the middle, where it is four-fifths as wide as 

 the head; length nearly equal to twice that of head, one-fifth longer than 

 broad; anterior and posterior margins slightly arcuate: sides evenly and 

 divergently arcuate before, moderately convergent and slightly sinuate be- 

 Stenini. 2 



