places in synonymy with congener, discolor Harr., ambiguus Say, 

 fossiger Mots., morosus Lee., inscriptus Cr. and phaeopterus Kby. 

 As a matter of fact not one of these species is the same as congener, 

 and they are for the most part mutually distinct among themselves. 



A. approximatus new species. 



Evenly oval, a little more broadly so than in congener, with which it is closely 

 allied. In all specimens seen the elytra are yellowish brown, the disk much less 

 deeply infuscate than is the rule in congener; elytral sculpture and lustre not 

 appreciably different in the sexes. The coxal plates are slightly larger than in 

 congener, their distance from the middle coxae being about half their own length, 

 this distance slightly greater in congener; other differences as indicated in the 

 table. The male tarsi and tarsal claws are as in congener. Length 7 to 8 mm. 



Described from a considerable series of specimens in Mr. Sherman's 

 collection bearing label "Horsefly Pk. divide, Placerville Rd. San 

 Mig County, Colorado, 8,000 feet, July 13, 1885," and were taken I 

 think by either Mr. Hayward or Mr. Bowditch. The type is a male 

 in my own collection. A single male from Florissant Colorado 

 (Cockerell) is also assigned here. Specimens have more recently 

 been received from Mr. Knaus who took them at "The Mammouth, 

 Utah, top of Parowan Mts., 10,000 feet." 



The present species is also very close to inscriptus and discolor, but 

 is quite surely distinct by its less minute and better defined elytral 

 reticulation, and its narrow more strongly convex prosternal process ; 

 the coxal plates approach the middle coxal cavities much more closely 

 in discolor. 



A. discolor Harris, N. E. Farmer VII, 1828, p. 164. 



In form, color and general structure, closely similar to congener, but separable 

 with certainty by the larger coxal plates, which at their anterior limits are less 

 than half their own length from the mesocoxae. The apices of the antennal 

 joints, and of the terminal joints of the palpi are as a rule without or with but 

 faint trace of infuscation (distinctly dusky or blackish in congener) ; the elytral 

 reticulation is finer and more obsolete, the areolae less conspicuously unequal, 

 and only distinctly so in the baso-sutural region, becoming nearly equal toward 

 the sides and apex. The size averages quite distinctly smaller than in congener, 

 the larger specimens of discolor being comparable in this respect with the smaller 

 examples of the latter, and the elytra are oftener of a clearer and more uniform 

 yellow brown color, although as described by Harris they are typically "fuscous" 

 with "margin and base pale." The male tarsi and tarsal claws are very nearly 

 as described of congener. Length 6.5 to 7.5 mm. 



This species ranges from New England to Manitoba. . The following 

 localities have been noted. Wales, Maine (Frost) ; Vermont (Adams 

 see below) ; Hopkinton, Mass. (Frost) ; Cornwall and Milford, 

 Connecticut (Chamberlain) ; Warren and Washington Counties, New 

 York (Sherman) ; Lake Memphremagog, Canada (Dimmock) ; Bay- 

 field, Wisconsin (Wickham) ; Isle Royal, Lake Superior (Wickham) ; 



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