1854.] 45 



is quite perceptible, yet, as there are forms almost intermediate, and no other 

 character can be seen to separate it from the preceding, I think it expedient to 

 arrange it as one of the races of P. sinuatus. 



0. Thorace latitudine non breviore, postice angustato, et lateribus longius 

 sinuato, angulis posticis paulo prominulis; impressionibus basalibus profundiori- 

 bus. 



Middle States and Lake Superior. Although the difference between this and 

 P. sinuatus seems very considerable, in a large series of the form (*) they seem 

 to disappear ; 1 have therefore hesitated to propose a new name lor this, and 

 consider it, like the previous one, as a race under P. sinuatus. 



C d. 



A group containing winged species, evidently allied to P. exte n si collis 

 &c, but differing by having only three elytral punctures ; the feet and antennas 

 are entirely black. The thorax is flattened, moderately margined, the margin 

 growing broader towards the base; it is almost longer than wide, very slightly' 

 narrowed posteriorly, hardly sinuate on the sides, truncate at base, with the pos- 

 terior angles rectangular, not rounded ; the basal impressions are very long and 

 finely rugous ; the elytra are flattened, truncate at base, slightly sinuate at apex ; 

 the striae are deep and fine, the interstices flattish, the 3d with three impressed 

 punctures ; the antennas are filiform. 



12. P. f u n e b r i s, cyanescenti-niger, thorace latitudine non breviore, postice 

 subangu^tato, et lateribus subsinuato, angulis posticis rectis, basi utrfhque lon- 

 gius impresso, et confertim ruguloso, elytris opacis thorace duplo latioribus 

 parum convexis, striis subtilibus interstitiis planis, 3io tripunctato. Long. .4. 



San Diego, California: abundant in almost dry water courses. Very distinct 

 from all other species found within our territories. 



13. P. ae n e o 1 u s, subtus nigro-virescens, capite thoraceque obscure viridi- 

 aeneis, hoc latitudine non breviore, postice subangustato, lateribus late rotundatis, 

 angulis posticis rectis, basi utrinque longius impresso, et confertim ruguloso, 

 elytris planiusculis purpureo-nigris, nitidis, tripunctatis, striis tenuibus, pro- 

 fundis, interstitiis vix convexis. Long. *4. 



One specimen ; Oregon. Also sufficiently distinct from all our other species. 



C e. 



A group of extreme complexity, containing winged species of metallic colors, 

 bluish or greenUh, with the base of the antennas, the feet, and occasionally the 

 thorax rufous or pale piceous. The antennae are long and filiform ; the thorax 

 is occasionally a little longer than wide, never much narrowed posteriorly, the 

 margin fine, but strongly reflexed, moderately rounded on the sides; the base is 

 oblique each side, and the posterior angles are obtuse and sometimes moderately 

 rounded ; the basal impressions are long, and posteriorly are marked with a short 

 line. The elytra are elongate, about twice as wide as the thorax, scarcely sinu- 

 ate posteriorly, striae deep, but usually fine, the interstices hardly convex, the 

 third with four to seven punctures, varying in the same species. By arranging 

 the different forms as races under the more distinct species, this group appears 

 to be capable of being reduced to order. 



14. P. e x t e n s i c o 1 1 i s, supra asneo-viridis, nitidus thorace latitudine longiore, 

 postice paulo angustato, angulis posticis vix rotundatis, basi punctulata, impres- 

 sionibus basalibus tuberculo parum elevato intructis, elytris striis subtiliter ob- 

 solete punctulatis, interstitio3io 47 punctato, antennarum basi pedibusquerufis. 

 Long. -31 39. 



Lee. Aga^siz' Lake Superior, 205. 



Feronia extensicollis Say, Trans. Am. Phil. Soc. 2, 54. 



Feronia (Anchomenus) proximits Harris, New England Farmer, 1S2S, p. 132. 



Anchomenus extensicollis Dej. Sp. Gen. 3, 113. 



Ago/mm (Anchomenus) extensicollis Kirby, Fauna Bor. Am. 24. 



