1854.] 49 



Middle and Eastern States, rare. Sufficiently distinct from P. melanarius, by 

 the slightly bronzed color, more obtuse and more rounded posterior thoracic an- 

 gles, and less deep and impunctured elytral striae. From P. metallescens, which 

 it resembles in the form of the thorax, it is easily known by the smooth elytral 

 striae and more dull color. From P. moerens, it is distinguished by the wider 

 thorax with more rounded base and less distinct posterior angles. 



Dr. Harris sent a specimen as Ag. collare Say ; the impunctured striae, how- 

 ever, prevent it from being referred to the species described by him under the 

 same name in the Trans. Am. Phil. Soc. as above quoted. 



25. P. Harrisii, niger, nitidus, thorace latitudine paulo breviore, subro- 

 tundato, basi late rotundata, angulis posticis obtusis, rotundatis, margine angus- 

 tius depresso vix reflexo, impressionibus basalibus latis, subrugosis, minus pro- 

 fundis, tuberculo obsoleto instructis, elytris paulo inaequalibus, thorace sesqui 

 latioribus, tripunctatis, striis impunctatis. Long. *35 *4. 



Agonnm Harrisii Lee. Ann. Lye. 4, 225. 



Massachusetts and Lake Superior. The inequalities of the elytra are pro- 

 duced by irregular dilated shallow impressions along the course of the striae : the 

 most obvious of these is usually near the extremity of the fifth striae : Dr. Harris 

 regards this as specific, and therefore applied to the species the unpublished 

 name Ag. sulcatum. The thorax is less transverse and less rounded than in the 

 preceding species, and the sides are less distinctly reflexed towards the base. 

 The second elytral puncture is on the second stria. 



26. P. pice us, rufo-piceus, nitidus, antennis capite thoraceque supra ob- 

 scuris, hoc quadrato-rotundato, latitudine paulo breviore, basi late rotundata, 

 angulis posticis obtusis vix rotundatis, marine anguste depresso vix reflexo, im- 

 pressionibus basalibus latis, minus profundis, elytris thorace vix sesqui latiori- 

 bus tripunctatis, striis sat profundis. Long. *28. 



Agouum piceum Lee. Ann. Lye. 4, 226. 



Massachusetts, Dr. Harris. Although differing in size and color, so as to pre- 

 sent no resemblance whatever to P. Harrisii, the form and structure is very 

 much as in that species : the posterior angles of the thorax are more distinct, 

 and the elytral striae deeper : as in that species, the second elytral puncture is 

 in the second stria. 



27. P. car bo, niger, nitidus, thorace subrotundato, latitudine paulo bre- 

 viore, basi vix late rotundata, angulis posticis obtusis rotundatis, margine angus- 

 tissime reflexo, impressionibus basalibus minus dilatatis, sat profundis, elytris 

 thorace vix sesqui latioribus convexiusculis, tenuiter striatis, tripunctatis. 

 Long. -35. 



Lee. Agassiz' Lake Superior, 205. 



One specimen, from the northern shore of Lake Superior. Differs from all 

 the preceding species by the narrower and slightly thickened reflexed margin of 

 the thorax. It approaches otherwise perhaps most nearly to P. tenuis : the 

 second elytral puncture is very near the second stria, but not in it, as in the tw r o 

 preceding species. 



28. P. atratus, niger, nitidus, thorace fere rotundato, latitudine paulo bre- 

 viore, basi rotundata, angulis posticis rotundatis, indistinctis, margine reflexo 

 postice paulo latiore, impressionibus basalibus latis tuberculo obsoleto instructis, 

 elytris thorace paulo latioribus, convexiusculis, tripunctatis, striis sat profundis. 

 Long. -34. 



Lee. Agassiz 5 Lake Superior, 205. 



Northern shore of Lake Superior. The thorax perhaps most nearly resembles 

 that of P. melanarius, but the base is more rounded, and the basal angles hardly 

 to be determined : the elytra are but little wider than the thorax, and more con- - 

 vex, giving the insect very much the form of Pterostichus erythropus. In one 

 specimen the striae of the elytra are impunctured, in another they are obsoletely 

 punctulate. 



29. P. frater, niger, nitidus, thorace transverso,subquadrato, basi vix late 



