AMERICAN COLEOPTERA. 61 



Incisure of hind angles deep, appendage long fi. pcrcomis. 



Incisure of hind angles shallow, appendage short 7. Tulnerata. 



D. — Base of prothorax not lobed, broadly reflexed, as usual; excavation en- 

 tirely lateral, anterior angle of incisure nearly rectangular, hind angle long, 

 acute, produced into a slender filament which is bent forwards. 



Elytra and prothorax pale, the latter sometimes with a black vitta. 



8. Iiifoa. 

 Black, prothorax yellow, sometimes with a black dorsal vitta... 9. filigera.. 



S. »<>pinigera. — Elongate, testaceous, head, antennae, elytra towards the 

 tip, and legs more or less dusky; prothorax smooth, shining, wider than long, 

 convex, strongly margined, deeply excavated and emargina'te each side near 

 the base, angles before and behind the emargination acute ; armed in addition 

 with a slender sharp spine near the hind angles; elytra finely scabrous and 

 pubescent; antennae with the 2d joint small, 3d equal to the 4th. Length .28 

 inch ; 7 mm. 



One % Oregon. The basal excavations of the prothorax are large, 

 deep and rounded. 



S. flavida. — Elongate, black, prothorax, elytra and feet yellow, the 

 former nearly twice as wide as long, sides straicjht oblique, front margin 

 broadly rounded, feebly reflexed, disc convex, hind fnargin blackish strongly 

 d3pressed and reflexed, deeply foveate each side; hind angles very deefily in- 

 cised, anterior process narrow acute; elytra du^ky towards the tip and sides, 

 finely not deeply punctured; tarsi and hind thighs dusky; antennae black 

 ( '^ ) as long as the body, 2d joint small, 3d and following ones equal. Length 

 6 mm. 



Two % , California, at Lake Tahoe. Similar in appearance to S. 

 pallida, but quite different by the deep incisure of the hind angles of 

 the prothorax ; penultimate ventral segment, as usual, deeply and 

 widely emarginate. 



S. cava. — Elongate, pale testaceous, prothorax much wid^r than long, 

 sides oblique, deeply emarginate near the base, angle in front of emargination 

 well defined, obtuse, basal angle produced into a compressed process which is 

 rounded at tip; disc strongly margined, deeply channelled, very deeply exca- 

 vated at the base each side; elytra finely scabrous and pubescent; occipiit 

 blackish; antennae and legs more or less dusky, the former slender with the 

 2d joint small, 3d equal to the 4th. Length .2 inch ; 5 mm. 



One S , Oregon. Smaller than »S'. palfufa with the sides of the 

 prothorax oblique not rounded and the basal foveas much deeper. 



S. vnlncrata. — Less slender, black, prothorax strongly margined, broad- 

 ly rounded on the sides, broadly excavated each side at the base, emargination 

 not very deep, angle in front obtuse, basal angle obliquely earinate, pmcess 

 short and rounded; disc feebly channelled with a reddish-yellow round spot 

 each side; elytra finely scabrous and pubescent; antennae short, 2d joint 

 small, 3d equal to the 4th. Length .25 inch ; 6 mm. 



