82 DURHAM DIPTERA. 



XIII, 134. 



8 (7). Side stripes on the dorsum curved outwards at their 



front ends. 



9 (10). Pleurae before the halteres (metapleurae) yellow, with 



a blackish brown spot on the under side only. 

 793. Pachyrrhina histrio, F. 

 Harperley, 4 $, 2 ?, 28-6-02. 



10 (9). Metapleurae yellow, but blackish brown on three sides. 



794. Pachyrrhina maculosa, Mg. 

 Bishop Auckland, 2 ?, 12-6-00, 4-7-01 ; Bollihope, 

 1 ?, 15-6-01. 



11 (6). Stigma distinct, blackish brown. 



12 (19). Side stripes on the dorsum curved outwards at their ends. 



13 (18). X.5. and V.5 3 not clouded. 



14 (17). Pleurae with blackish markings. 



15 (16). The vertical triangle nearly equilateral. 



795. Pachyrrhina cornicina, L. 

 Bishop Auckland, 2 $, 25/27-6-02; Harperley, 1 $, 

 28-6-02. 



16 (15). Vertical triangle produced forwards in a long point. 



796. Pachyrrhina guestfalica, Westh. 

 Bishop Auckland, 1 ?, 4-7-01. 



17 (14). Pleurae with reddish brown markings. 



797. Pachyrrhina analis, Schum. 

 Bishop Auckland, 1 <£, 1 -02. 



18 (13). X.5. and V.5 3 clouded. 



798. Pachyrrhina quadrifaria, Mg. 

 The commonest species in this district. 



19 (12). Side stripes on the dorsum straight. 



800. Pachyrrhina lunulicomis, Schum. 

 Bishop Auckland, 1 $, 26-6-02 ; Harperley, 1 $, 

 28-6-02. 



20 (5). Abdomen without any central line. 



799. Pachyrrhina annulicornis, Mg. 

 Harperley, r $, 28-6-02. 



