ART. 28 REVISIOX OF DISOXYCHA NORTH OF MEXICO BLAKE 13 



a wide band, elytra with wide and dark sutural, median, and sub- 

 marginal vittae. Head with interocular space more than half width 

 of head; frontal tubercles well marked, carina narrow, somewhat 

 produced; surface smooth and shining, except a deep fovea sur- 

 rounded by coarse punctures on each side near eye; usualh' entirely 

 dark except the base of the antennae, but sometimes a narrow pale 

 streak along lower edge of front. Antennae long (for the genus), 

 dark, third and fifth joints subequal and shorter than fourth. Pro- 

 thorax about twice as wide as long, nearly rectangular, with sides 

 only slightly arcuate, not very convex and with a slight basal median 

 depression; surface somewhat shining, under high magnification 

 finely alutaceous and indistinctly punctate; pale with median dark 

 spot, this sometimes broadening to form a wide band across prono- 

 tum, leaving margin always pale. Scutellum dark. Elytra oblong 

 oval with parallel sides; not very convex, humeri marked by short 

 intrahumeral sulcus ; in the female 3 or 4 costae on each elytron, not 

 so long or so prominent as in conjugata, these costae not apparent in 

 the male ; surface smooth, somewhat shining, under high magnification 

 indistinctly alutaceous, and very finely punctate; pale with very 

 broad sutural, median, and submarginal vittae, the submarginal and 

 sutural usually broadly united at apex, the paler intervening vittae 

 much narrower than the dark ones. Body beneath finely pubescent 

 and entirely dark except the sides of the presternum and the last 

 ventral segment, sometimes margin of the penultimate segment also 

 pale. Length, 5 to 6 mm; width, 2.8 to 3 mm. 



Type locality. — Pennsylvania. 



Distribution. -^ — Massachusetts (Framingham, Nantucket) ; New 

 Jersey (Boonton) ; Maryland (Glen Echo) ; Virginia (Fredericks- 

 burg, Norfolk) ; North Carolina (Chadbourn) ; Florida (Bradenton, 

 Capron, Crescent City, Daytona, Enterprise, Lake Harne}', Lakeland, 

 Key West) ; Illinois (Pulaski, Running Lake, Urbana) ; Alabama 

 (Mobile) ; Louisiana (Mandeville, New Orleans) ; Texas (Avery, 

 Dayton, Mineola). 



Food plant. — Polygonum sp. (C. W. Johnson). 



Remarks. — Although Illiger's description of penmjlvamca is un- 

 usually detailed and definite, this species has long been confused with 

 two larger species, uniguttata and procera. It is usually smaller and 

 darker than either of these, having an entirely dark head and legs, 

 and the undersurface, except the last one or two ventral segments 

 and sides of presternum , is entirely dark. Unlike uniguttata., it 

 has the elytral punctation very fine and indistinct. No specimens 

 are yet known from west of the Mississippi River except in Louisi- 

 ana and Texas. 



** The statements of distribution are based on specimens examined by the author. 



