18 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 82 



Description. — Elongate oblong oval, somewhat shining; elytra dis- 

 tinctly punctate; head sometimes entirely dark but usually pale in 

 region about antennal sockets and lower front, pronotum usually 

 with large median spot and two paler brown lateral spots, these 

 sometimes banded together; elytra with wide sutural, median, and 

 submarginal vittae, usually margin of abdomen and femora pale, but 

 these sometimes also dark. Head with interocular space more than 

 half width of head, frontal carina narrowly produced, tubercles 

 well marked; surface generally smooth except for the coarse punc- 

 tures about fovea on each side near eye and often a fovea in middle 

 of vertex; usually black with a paler area about antennal sockets 

 and lower front and a median dark streak on carina. Antennae 

 dark with paler basal joints, robust, long for the genus, third joint 

 shorter than fourth or fifth, which are subequal, the fourth slightly 

 longer. Prothorax about twice as wide as long, slightly narrowed 

 anteriorly with arcuate sides; not very convex, with a prominent 

 callosity on either side and a median basal depression; surface alu- 

 taceous and finely punctate ; pale, usually with a large median spot, 

 wider anteriorly, and two paler lateral spots, sometimes all coales- 

 cing to form a wide band across pronotum, sometimes the lateral 

 spots vanishing. Scutellum dark. Elytra with sides parallel, hu- 

 meri marked by short intrahumeral sulcus; in female sometimes 

 traces of costae, but these not so pronounced as in conjugata\ sur- 

 face alutaceous and distinctly and rather densely punctate; dark 

 elytral vittae considerably wider than intervening pale one, the 

 sutural and submarginal rarely united at apex. Body beneath finely 

 pubescent, sometimes undersurface and legs entirely dark, but usu- 

 ally abdomen with a pale margin and femora pale. Length, 5.8 to 

 8 mm; width, 2.2 to 3.8 mm. 



Type locality. — United States. 



DistHhution. — Massachusetts (Chicopee, Hopkinton, Natick, Way- 

 land, Weston) ; Rhode Island (Watch Hill) ; New York (Staten 

 Island, Whiteface) ; New Jersey (Boonton, Palisades) ; Pennsyl- 

 vania; District of Columbia; Virginia (Arlington); Tennessee; 

 Kentucky; Georgia; Florida (Gainesville); Louisiana (New Or- 

 leans) ; Michigan (Detroit, Monroe) ; Indiana (Hessville, Osborne, 

 Pine) ; Illinois (Algonquin, Chicago, Devils Neck, Flag Lake, Forest 

 City, Grass Lake, Griggsville, Havana, Normal, Quincy, Thompson 

 Lake, Urbana) ; Wisconsin (Madison) ; Iowa (Ames) ; Missouri 

 (Flat River, Kansas City, St. Louis) ; Kansas (Douglas County, 

 Topeka) ; Nebraska; Manitoba (Treesbank, Winnipeg). 



Food plant. — Polygonum sp. (C. A. Frost). 



Remarks. — This species has been commonly called pensylvanica 

 (usually but not originally spelled '"'' peunsyhianica'''') but, although 



