NORTH AMERICAN COLEOPTERA. 125 



In the uncertaicty from want of specimens of many foreign genera, 

 and from the fact that our small fauna hardly requires the separation 

 of genera in groups, I refrain from indicating a new group. 



Phyllecthrus is peculiar to our fauna, and contains but few species, 

 which may be separated in the following manner : 



Anteunse dissimilar in form in the two sexes, thickened toward the tip % or 

 filiform 9 . l'"Jt 11-joiuted in both sexes. 

 Scutelliim yellow; elytra comparatively smooth. 



Elytra wider than the thorax ; auteuiise piceous in both sexes. ..dorsalis. 

 Elytra not wider than the thorax ; antennte quite pale % , and but little 



darker 9 paralleliis. 



Scutellum black ; elytra vaguely subsulcate and distinctly punctate. 

 Elytra a little wider than thorax ; antennae brown % , piceous 9 • 



subsulcatas. 

 Antennae filiform iu both sexes and piceous, but 10-jointed % , 11-jointed 9 . 

 Elytra distinctly wider than the thorax and quite smooth ; scutellum yellow. 



geutilis. 



F. clorsalis Oliv., Ent. vi, p. 646, pi. 4, fig. 54 ; atriventris Say (partim), 

 Journ. Acad, iii, p. 461; ed. Lee. ii, p. 224; Lee, Proc. Acad. 1865, p. 207. — Head, 

 thorax and underside of body yellow, elytra and abdomen black, thorax some- 

 times with a piceous stripe each side. Antenuje black. Head smooth. Thorax 

 broader than long, sides slightly arcuate at front angles, nearly parallel behind, 

 disc convex, with a vague shallow impression each side, surface smooth ; scutel- 

 lum yellow. Elytra black, shining, usually impunctate, sometimes sparsely 

 punctate. Body beneath quite smooth, abdomen sparsely, finely punctate ; 

 femora yellow, tipped with black, tibiae and tarsi black. Length .24 inch. ; 6 mm. 



Male. — Antennae 11-joiuted, gradually thicker to apex, joints 2 and 3 small 

 and equal, together shorter thau the fourth, the fourth but little shorter than 

 the first, eighth joint shorter than the seventh or ninth; middle tibiae deeply 

 notched ou the iunerside near the apex; first joint of anterior tarsus shorter 

 than the second ; second ventral with a conical process from the middle of the 

 posterior edge. 



Female- -Antenn?& slender, 11-jointed, joints 2 and 3 together equal to the 

 fourth, joints 4-11 nearly equal in length; middle tibiae simple; first joint of 

 front tarsi fully as long as the second. 



Variations. — Specimens occur with the broad piceous band rjear 

 the side of the thorax, or with the thorax entirely yellow. The latter 

 are more generally females. Specimens occur with almost the under- 

 side of the body piceous, including the legs. The elytra may be 

 absolutely smooth or punctate, my specimens showing the former to 

 be female and the latter male, but sufficient material is not at hand 

 to say if the character is really sexual. 



There seems to be very little doubt that Say has confused two 

 species iu his atriventrU. The general description, except as to the 

 color of the antennae, will fit this species or nigripennix Lee, but the 



TKANS. AM. ENT. SOC. XX. JUNE, 1893. 



