302 



F. W. EDWARDS. 



and the anal gills are very small and globular, not a quarter as long as the saddle. 

 Whether these characters distinguish A . dorsalis as a species or merely the American 

 race remains to be proved. 



Distribution. — Coasts of northern Europe from France and southern England 

 to Norway and the Baltic ; Central European plain, and thence westward across 

 Central Asia, China and North America as far as the Atlantic coast ; North Africa 

 (according to Macquart). 



Some localities from which I have examined specimens are : — Denmark {Wesen- 

 berg-Limd) ; Sweden (Ostergotland, Haghmd) ; Finland (Kexholm, Eriksberg, 

 Uskela, E. J. Bonsd. ; Kuusto, Lundstrom ; Soroka, /. Sahlberg) ; Germany 

 (Berlin, Meigen, Enderlein ; Usedom, Stilldorf, Lichtivardt ; Halle, Loew) ; Austria 

 (Hainfeld, Mik) ; Hungary (Budapest, Kertesz ; Budafok, Bartko ; Fehertelep, 

 Ujhelyi ; Torda, Biro ; Keczel, Hild, Thalhammer ; Neusiedler-See, Handlirsch) ; 

 North Russia (Waloniki, VcUtchkovsky) ; Mongolia (" Vallee pres de la Koure de 

 Bandie, 1500 m." and " Bords du Tarim," Mission de Lacoste, Dr. dn Chazand, 

 1909) ; Siberia (Irkutsk, Schulz) ; North China (Tinghai, C. Ford). 



Fl£ 



Aides mariae (Scrg.), end of abdomen of larva; comb and pccten teeth and mentum 

 more highly magnified. 



