^^^ NEW YORK STATE MUSEUM 



TXT^t- ^ ^""ff' '""' °'^"'^' ^^ ""=S as the abdomen 



m fiesh specimens; usually longer than the abdomen in dried 

 specimens; cinereous in color, the anterior veins conspicuous 

 bro,rn,sh or black; media and cubitus pale, posterior miTn' 

 very delicately ciliate. Halteres usually pate, i„ an occSa" 



5 mm. (j)1.30, fig.lS), 



Female Cinereous black, front and epistome cinereous, bt^s 

 but shght y e:.cavated at base of antennae; palpi and antenSe 

 fuscous the latter with 8 joints counting the disk-like rsal 

 joint, short-haired (pl.P, fio-j) ; scutellum hemispherical dark 

 brown, with black setae; abdomen fuscous with' 2Jtb. own 

 bans, posterior margins to the segments darker except on the 



i:'rZ ^'"' T'"' " ""f' ^^""^"' ^'""''^''^ ^--1^' brown and 

 ieaf-like, legs fuscous; claws simple; wings broad, and lon-er 



en °tl -Trl '"'"' ""^^'^ ^"^"^ ^^^^^' "^^'^'^ ^-^ cubitus pale; 

 Sm bred .nd ""; ^ '*''•' ''''''''' ^^^^ ^^^ -^^^- ^^^-i^ed 



rn^v f '/ ^ i ^' « ^^ « "1 ^^ s n i V o r i u n d u s , which I formerly 

 considered a synonym of I) i a mesa waltlii Meio- i now 

 regard as distinct. ^*' ^^ 



According to Lundbeck (1898), D. wa 1 1 1 i i does not possess 

 ciha on the posterior margin of the wing, he quoting Meigen as 

 authority for this statement; the European specimens,' however, 

 which I have do possess these cilia, as do also my American speci- 

 mens. The cilia are quite short and rather difficult to see with a 

 hand lens D. aberrata Lundbeck (1898, p.290), according 

 to Its author, differs primarily from D. w a 1 1 1 i i in possessing 

 ciha on the posterior margin of the wing; but since waltlii 

 does have the cilia, this distinction fails, and the two names must 

 be regarded as synonymous. In the description of aberrata 

 the scutellum and legs are said to be pale brown, while in 

 waltlii, as described above, they are dark brown or fuscous. 

 These differences are at most only varietal in character; and 

 furthermore, in immature specimens these parts are usually 

 somewhat paler than in mature specimens. 



2. Diamesa chorea Lundbeck 

 1898 Diamesa Lundbeck. Vidensk. Meddel. 291 



Greatly resembling D. a b e r r a t a Lundb.; its smaller size, 

 obscure coloring, white balteres and more slender legs will dis- 

 tinguish it. 



