148 BROOKLYN MUSEUM SCIENCE BULLETIN 3. 3. 
occasionally prominent; posterior angles moderately prominent; lateral 
tubercles distinct, though often scarcely prominent laterally, more or 
less distinctly separated from the disk by a shallow arcuate impression; 
sides below the tubercles feebly converging and more or less distinctly 
arcuate; median impressed line fine when present but generally absent; 
basal impression usually distinct; surface finely rugose or very finely 
strigate-rugose with or without visible punctuation. 
Elytra shining with at most feeble dorsal impressions ; with or with 
scarcely any transverse coarser rugae ; intervals finely punctate or finely, 
rugose ; lateral margin from a postero-lateral view more or less distinctly 
acute at about basal half or less, but generally not even but interrupted. 
Body below densely and finely punctate and sparsely pubescent with 
short, white hairs; side pieces of prosternum finely and more or less 
distinctly strigate-rugose; posterior femora extending to or nearly to 
the apex of the third ventral segment, distinctly but not strongly clavate, 
at base generally narrower than at apex, armed below usually with a 
small tooth in both sexes, which is rarely absent. Length: 5.5-6.5 mm. 
Male: First ventral segment more or less deeply excavated along 
middle, but generally more deeply anteriorly; last ventral segment 
depressed at middle of apex; last dorsal segment more or less distinctly, 
broadly emarginate at apex, rarely truncate. 
Female: Last ventral and dorsal segments broadly rounded at 
apex; lower vaginal plate nearly as in emarginata. 
Type, a male, and allotype, a female, in the Museum coll. ; paratypes 
in collections of the Nat. Museum and Mr. Wallis. 
Alaska: Popoff Island, July (Kinkaid in Nat. Mus.); Kutmai, July 
(Hine). 
Alberta: Banff, June (Van Dyke); Edmonton, June (Carr). 
Manitoba: Aweme, July (Criddle) ; Huds. B. Ry. from miles 17-332, 
June (Wallis); Rembrandt, May (Mrs. Mulligan in coll. Wallis). 
Wyoming: Como; Yellowstone Pk., July (Nichol in coll. Minn. Univ.). 
Minnesota: Duluth, Hennepin Co., and Ottertl Co. (Minn. Univ.). 
Michigan: Marquette (Hubbard and Schwarz). 
Huds. Bay. Terr.: "H. B. T." (Leconte coll.). 
Specimens of this species in the collection of Mr. Wallis were labelled 
"on flowers of Caltha palustris (Mrs. Mulligan)." 
From the smaller species with rugose prothorax, bicolored or pale 
posterior femora armed with a small tooth wallisi differs in being of 
more elongate and narrower form, longer antennal joints and sculpture 
of prothorax finer. D. fulvipes has a large tooth on posterior femora and 
