1873.] . o£±. [Horn. 



Fourth dorsal feebly arched at base, not joining the 

 sutural, the latter short, rarely extending beyond 

 the punctured region ; interatrial region coarsely 



and densely punctured lugens. 



Fourth dorsal strongly arched at base, usually joining 

 the sutural, interstrial region very slightly or not 

 punctured. 

 Sutural stria wanting at basal and apical portions, 



visible for a very slight extent at middle only imperfectus. 



Sutural stria distinctly impressed at apical portion, 

 and joining the apical marginal stria. 

 Surface metallic ; interstrial spaces not punctured ; 



prosternum strongly convex pensylvanicus. 



Surface piceous or slightly bronzed ; interstrial 

 space more or less punctured; prosternum feebly 

 convex. 



Elytral punctures aciculate or veiy dense oregonensis. 



Elytral punctures sparse and distinct. 



Internal subhumeral and humeral continuous... impressus. 

 Internal subhumeral not continuous with hume- 

 ral infaustus. 



S. alienu.3, Lee. Ann. Lye. V., p. 167. 



Broadly oval, robust, black, with slight bronze tinge, antenna? and 

 anterior legs reddish-brown. Head densely aud coarsely punctured, 

 supra-orbital stria distinct, not advancing across the front. Thorax with 

 slight impression near the anterior angles, disc smooth, at sides punc- 

 tured, punctures dense and coarser nearer the margin, at base with very 

 few punctures, especially at middle. First dorsal stria of elytra extend- 

 ing slightly beyond the middle, second, third and fourth gradually 

 shorter, fourth not arched at base, sutural very fine and entire ; external 

 subhumeral short, deeply impressed, not joining the marginal, humeral 

 fine, joining the short internal subhumeral; indexed portion of elytra with 

 the marginal and two epipleural stria? ; surface with the space between 

 the stria> opaque, not densely punctured, the punctures and opacity 

 following nearly the curve of the inner dorsal stria to the apex of the 

 suture. Propygidium and pygidium moderately punctured, the latter 

 more sparsely at apex. Anterior tibia? finely 6-denticulate, middle and 

 hind tibiae finely biseriately spinulose. Prosternum smooth, feebly eon- 

 vex, stria? scarcely ascendant, gradually divergent in front. Length 

 . 14-. 16 inch ; 3.5-4 mm. 



This species is one of the most readily known of the group. It had 

 been placed in Group I., with which it has indeed considerable resem- 

 blance, and has been separated solely on account of the form of the hind 

 tibia? of the unique species of that Group. 



Occurs at San Diego, and in Owen's Valley, California. 



A. p. s. — vol. xiii. 2o 



