OSTEN SACKEN ON WESTERN DIPTERA. 313 



greenish-black stripe on the outside ; tarsi infuscated from the tip of the 

 first joint; hind tibiae slightly incrassated, on the inner side glabrous, and 

 with a longitudinal furrow, the bo ttom of which is brownish. Wings 

 grayish, slightly tinged with yellowish anteriorly, except the costal cell, 

 which is subhyaline ; costa with a stout swelling at the tip of the first 

 vein; the posterior margin deeply indented at the end of the fourth vein. 

 Female. — The antennae are a little smaller and less hairy, although 

 they have the same structure and coloring ; the face is broader; the hind 

 tibiae are not incrassate and not glabrous on the inner side; the costa is 

 without sw elling; the indentation of the posterior alar margin is pres- 

 ent. Length 6-7 mm . 



Hal). — Los Guilucos, Sonoma County, California, July 5. Two males 

 and one female. 



2. HYanoCELEUTHUS afflictus n. sp. — Male. — Similar in all re- 

 spects to the preceding species, except that the antennas are not much 

 larger and not much more hairy than those of an ordinary Dolichopus ; 

 the first joint has the same yellow expansion on the inner side ; the sec- 

 ond joint is much smaller, and has only a vestige of yellow on the inner 

 side; the pubescence of the arista is so fine as to require a much 

 stronger magnifying power; the face is silvery- white ; the cilia of the 

 1 inferior orbit almost white; lamellae of the hypopygium whitish. The 

 i hind tibiae of the male have the same structure, only they are a little 

 ; more incrassated and the shallow groove on their inside is broader and 

 more distinctly tinged with brown ; on each side of the second abdom- 

 inal segment, there is a tuft of long yellow hair, which does not exist 

 in my specimens of S. crenatus; the wings are the same as in the latter 

 species. Length 6-7 mm . 

 Sab. — San Eafael, Cal., May 19, A single male. 

 Observation. — Dolicliopus lamellicomis Thomson, Eugenies Eesa, etc., 

 511, 114 (a female), judging from the description of the antennae, 

 must be a Sygroeeleuthus. The description does not agree with my 

 female of H. crenatus; but it may be the female of R. afflictus, which I 

 do not possess. All the characteristic marks of the species do not, of 

 course, exist in the female, which the author describes ; but he does not 

 even mention the indentation on the hind margin of the wing, which 

 in S. crenatus at least exists in both sexes ; and, if the same is the case 

 with the unknown female of S. afflictus, this would exclude the synon- 

 ymy of Mr. Thomson's species. 



. DOLTCHOPUS. 



The three species of Dolicliopus before me, after comparison with the 

 analytical table of the Eastern American species, in the Monographs, 

 etc., vol. ii, 323, may be tabulated as follows: — 



il. Prevailing color of the legs black ; cilia of the inferior orbit black : 

 1 . corax n. sp. 



