102 GEO. H. nORN, M. D. 



spur. Tarsi with fourth joint bilobed, the first joint of the posterior 

 as long as all the others. Claws simple. 



The outer edge of the tibiae is flattened and acutely limited each 

 side. The labial palpi show a tendency to vary somewhat in struc- 

 ture. Usually the third joint is inserted at the middle of the side 

 of the second, but in Troherti the second joint is rather stout, very 

 obliquely truncate, and the third is inserted in the truncation. The 

 head beneath has the subocular ridge in orbiculatus alone. 



Our species as far as known are : 



Head beneath without subocular ridge. 



Color above uniformly piceous tibialis. 



Color testaceous, elytra with short brown lines. (PI. I, fig. 15)...Troberti. 

 Head beneath with subocular ridge. 



Color of elytra piceous with common central red spot orbiciilatus. 



S. tibialis Guer. — Broadly oval, piceous or nearly black, moderately shin- 

 ing, sparsely pubescent. Head and thorax nearly smooth. Elytra moderately 

 densely punctulate. Body beneath moderately densely punctulate. Femora 

 piceous, tibise, tarsi, palpi and antennse paler. Length .10 — .14 inch; 2.5 — 

 8.5 mm. 



Occurs in the more northern States and Canada, and very closely 

 allied to the European hemisphericus. 



S. Troberti Guer.— Broadly oval, moderately convex, brownish testaceous, 

 very feebly pubescent. Head and thorax moderately densely punctate. Thorax 

 brownish testaceous with paler spaces. Elytra more coarsely punctured than 

 the thorax, pale testaceous with brownish longitudinal lines forming three 

 irregular dentate bands, basal, median and subapical. Body beneath brownish 

 testaceous, moderately densely punctulate. Length .20 — .22 inch : 5 — 6.5 mm. 

 (PI. I, fig. 15). 



Differs from our other species by the larger size and its coloration. 

 Occurs in Texas and Mexico. 



S. orbiculatus Fab. — Broadly oval, black or piceous, moderately shining, 

 sparsely pubescent. Head and thorax sparsely punctate. Elytra more coarsely 

 punctured than the thorax. Body beneath moderately densely punctulate. 

 Femora piceous, tibise, tarsi and autennse pale. Length .10 — .12 inch; 2.5 — 

 3 mm. 



This spofies varies considerably in color giving rise to several 

 synonyms, these are as follows : 



orbiculatus: Fab. — Sides of the thorax and common central spot of 

 elytra reddish-yellow; centralis Say, lateralis Lee, suturalis Zieg. 



suturalis Gu6r. — Thorax entirely piceous. 



rxijicollis Lee. — Thorax entirely yellow, elytra pale from imma- 

 turity but showing the common central spot. 



Occurs from the Middle States to New Mexico. 



