164 Journal Nkw York Entomological Society. [Vol. xxvi. 



Black with orange yellow prothorax. (Atlanta, Ida., Garland, Col., and 



high Sierras of Cal.) S. spinigera var. munita Lee. 



4 — Black with disc of prothorax reddish yellow. (L. Superior, Hudson Bay 

 Region, Col., N. Mex., Northern Ariz., Cascades of Wash., Kaweah, 



Cal.) S. difficilis Lee. 



Black with pronotum orange and elytra except apices and most of legs 

 testaceous. (Cascades and Sierra Nevada Mts.) 



S. difficilis var. flavida Lee. 

 Entirely black. (Very high Southern Sierras of Cal.) 



S. difficilis var. carbo n. var. 

 5 — The anterior angle of armature not conspicuously projecting, the pos- 

 terior appendage always slightly ante-basal, at least at origin 6 



The anterior angle of armature formed into a more or less projecting 



appendage, the posterior appendage basal 15 



6 — The ante-basal process a more or less compressed process, blunt at apex../ 



The ante-basal process a mere filament 13 



7 — The lateral incisure narrow and moderately deep 8 



The lateral incisure broad 10 



8 — Ante-basal process arising close to base, moderately long, narrow and 

 straight, but blunt at apex, antennae over % length of body, color en- 

 tirely black. Length 5 mm. (Wash., Mt. Jefferson, Ore.)..S. atra Lee. 

 Ante-basal process broad, antennae barely reaching % length of body.... 9 

 9 — Upper surface pale yellow, ante-basal process straight and rather long, 

 elytra simply punctured. Length 5-7 mm. (Western Ore. and most 



of Cal.) S. cava Lee. 



Upper surface black with disc of pronotum yellow, ante-basal process 

 short and curxed, elytra scabrous. Length 4.5 mm. (Coastal area of 



North. Cal.) S. rugosa n. sp. 



10 — The incisure deep, the ante-basal process long, broad, and hardly curved, 

 black with disc of prothorax orange, antenna; barely reaching •)4 

 length of body. Length 5-6 mm. (Can., Mich., Ind., Ohio, Mass., 



Tex.) S. percomis Say. 



The incisure shallow, the ante-basal process short, narrow, and curved 



forwards, antennae longer than 3-4 of body 11 



II — Upper surface mostly pale yellow. Length 6 mm. (Western Ore. and 



north to Sitka, Alaska) S. pallida Mann. 



Upper surface black except disc of pronotum which is orange margined 



with black 12 



12 — Disc of prothorax without longitudinal impressed line, antennae robust, 

 elytra simply punctate, not rugose. Length 5 mm. (Coast belt of 



Oregon.) S. pallida var. maritima n. var. 



Disc of prothorax with distinct longitudinal impression, antennae finely 

 filiform, elytra coarsely punctate and rugose. Length 5 mm. (Eastern 



Wash, and Ore. to Col.) S. vulnerata Lee. 



13 — The ante-basal filamentous process long and cur\ed. reaching the an- 

 terior angle and completely enclosing the incisure 14 



