DURHAM DIPTERA. 10 1 



XVI. 157. 



abdomen connected with the black on the third 

 segment by a V-shaped mark on the second 

 segment. 



918. Chrysofis ccecutiens, L. 

 Witton, 1 ?, 12-7-99; Bishop Auckland, 6? July- 

 August, 1900-02. 



33 (32). All the tibiae, or at least the mid tibiae wholly and 



the mid and hind metatarsi brownish yellow. The 

 black entirely broken at the second segment, the 

 hind part of which is narrowly yellow all across. 



34 (35). Second abdominal segment with a broad rectangular 



spot in the middle in the male, or a small isolated 

 round spot in the female. (919- quadrata, Mg.) 



35 (34). Second abdominal segment with two black blunt 



triangles, like a solid w (W) — broad, and repeated 

 on the third and fourth segments in the male; small, 

 and with only interrupted black bands on the third 

 and fourth segments in the female. 

 920. Chrysops relicta, Mg. 

 2 $ and 3 ? were taken near Greatham by Mr. 

 Gardner, of Hartlepool. 



36 (31). The warts on the cheeks and jowls united, face and 



cheeks wholly shining black. 



(921. seftdchralis, F.) 



Family XVIL— LEPTID^. 



TABLE OF GENERA. 



1 (4) (7). Third antennal joint conical or round with a 



terminal bristle, long and usually bent (III. 10, 11). 



2 (3). 0.6. open. Leptis (158) 



3 (2). 0.6. closed. Chrysopilus (159) 



4 (1) (7). Third antennal joint kidney-shaped, with an 



apparently dorsal straight bristle (III., 12, 13). 



5 (6). O.6. open. Symphoromyia (162) 



6 (5). 0.6. closed. Atherix (160) 



7 (1) (4). Third antennal joint with a short terminal style 



(III. 14). 163. Spania (938. nigra, Mg.) 



