NORTH AMERICAN COLEOPTERA. 15 



A. riirioola Mels.— Obloiijr oval, someiimes slijilitly wider posteriorly, pic.e- 

 ous black, shinint;. Antenna; ferruginous, club darker. Head distinctly tritu- 

 berculate, sparsely punctate, in front slightly rugulose. Clypeus lieniil)exa<;onal, 

 bi'oadly eniarginate at middle, the angles on each side obtusely prominent, geme 

 feebly prominent and very obtuse. Thora.K convex, narrower in front, sides 

 feebly arcuate, the liiud angles distinct, rather obtuse, base regularly arcuate, 

 punctures of disc moderate, not densely placed, but very regularly disposed. 

 Elytra a little wider than the thorax, humeri obtu.se, disc rather deeply .striate, 

 striaj rather coarsely crenately punctured, intervals convex, very finely sparsely 

 punctate. Body beneath sparsely punctate. Posterior femora sparsely, finely 

 punctate. First joint of posterior tarsus very little longer than the next two. 

 Length .18-22 inch ; 4.5-5.5 mm. 



In the males the frontal tubercles are more distinct, the thorax 

 relatively larger and the spur of the anterior tibia rather stouter. 

 Ill the female the angles of the clypeus on each side of the emargina- 

 tion are more distinct. 



In the specimens from the more southern States the form is larger, 

 the elytra less deeply striate, the intervals flatter and more distinctly 

 punctulate. Specimens have been ob-served with the ajiices of the 

 elytra somewhat paler in color. The form described by Harold 

 (Berl. Zeitsch. 1863, 375) as aurelianus is the larger southern form. 



Occurs from Canada and N. E. States to Texas and Colorado. 



A. autJiraciniis Lee.— Oblong, moderately elongate, black, shining, legs 

 brownish. Antennte ferruginous, the club darkei-. Head moderately closely 

 punctate in the female, less so in the male, front indistinctly trituberculate. the 

 middle tubercle more prominent in the male. Clypeus hemihexagonal, anteriorly 

 emargiuate, more deeply in the male; the angles obtuse, sides oblique, genae 

 feebly prominent, but obtuse. Thorax convex, larger in the male, nari'ower in 

 front, sides arcuate, more strongly in the male, hind angles very distinct, but ob- 

 tuse; ba.se regularly arcuate, disc variably punctured in the sexes, rather densely 

 punctured with intermixed punctures in the female, nu)re sparsely i)unctured 

 and smoother in the male. Elytra as wide as the thorax, parallel, humeri dis- 

 tinct, but obtuse; disc striate, striaj closely punctured, intervals flat O or 

 .sliglitly convex % and with a row of fine imnctui'es on each side adjacent to the 

 strife. Body beneath sparsely punctate. Posterior fenu)ra spar.seiy jiunctate. 

 with a row of coarse punctures jiarallel with the posterior margin near the knee. 

 First joint of liind tarsus nearly equal to the next three. Length .28-. 30 inch ; 

 7-7.5 mm. 



In the male the thorax has the sides parallel behind the middle, 

 while in the female the thorax narrows from the base to the apex. 

 The only differences observed between the sexes other than those 

 noted above are found in the stouter anterior tibial s))ur and the 

 stouter upi^er spur of the middle tibia. 



By some accident, difficult to ex[)lain, Dr. LoConte has jjlaced this 

 species in the series with uiiequal spinnles. There can be no doubt. 



