Chaetoneurophora. 101 



Remarks: Becker says that he has seen a large niimber of spec- 

 imens without darkened apical part of the wing, and he refers such 

 specimens to a var. claripennis; he says nothing about the sex of these 

 specimens, but he states that he has seen a copulated pair the male 

 of which had clear wings, but the female had the apical part dark- 

 ened; in my material the males have always the wings without 

 darkening or rarely with a very slight indication of a darkening, 

 while the females always have the darkening, but sometimes rather 

 faint, and Malloch (Ent. Month. Mag. 2, XIX, 12) notes the same. 

 Becker ascribes to the species two long bristles on the jowls, but 

 there is (as in the other species of the genus) only one long lower 

 postocular bristle. — One of my female specimens shows on the left 

 hind tibiæ five bristles of which three dorsal, and on the right six, 

 three anterodorsal and three more dorsal. 



4. Ch. caliginosa Meig. 



1830. Meig. Syst. Besctir. VI, 214, 6 {Phora). - 1910. Kertész, Cat. 

 Dipt. VII, 390 {Phora). - 1912. Malloch, Proc. U. S. Nat. Mus. 43, 424. — 

 1914. Brues, Bull. Wisc. Nat. Hist. Soc. XII, 87. — 1918. Schmitz, Jaarb. 

 Natmxrh. Genootsch. Limburg 1917, 91. — Phora urhana Meig. 1830. 1. c. VI, 

 215, 11. — 1848. Zett. Dipt. Scand. VII, 2856, 5 {Trineura). - 1864. Schin. 

 F. A. II, 342. — 1901. Beck. Abhandl. zool. bot. Gesell. Wien, I, 21, 7, Taf. I, 

 Fig. 9. — 1906. Wood, Ent. Month. Mag. 2, XVII, 194. — Trineura trochanterata 

 Zett. 1855. 1. c. XII, 4822, 5-6. 



Male. Frons considerably broader than high, black, a little shin- 

 ing; bristles strong, the anterior row^ more or less convex. Antennæ 

 black, of medium size; arista long, very short-pubescent, apparently 

 nude. Palpi brown or dark yellowish brown, with ordinary bristles. 

 Genal bristles 3 — 5. Thorax black, shining, with black pubescence 

 and one pair of dorsocentral bristles. Pleura with the upper margin 

 of pteropleura whitish. Abdomen black, somewhat greyish, first seg- 

 ment somewhat pale on the middle, second and sixtli segments elong- 

 ated, the three intermediate short and increasing in length backwards; 

 abdomen sparingly clothed with short, black hairs, forming a row at 

 the hind margin of the segments; second segment with a few longer 

 hairs at the hind corners, and sixth segment with longish hairs at 

 the hind margin. Hypopygium somewhat large, greyish black, with 

 short hairs; it is constructed as in thoracica; anal tube quite short, 

 brownish, with longish hairs. Legs brownish, femora more blackish 

 brown, knees yellowish ; front tibiæ with a dorsal bristle a little above 



