DIPTERA SCOTICA : VI. THE WESTERN ISLES 205 



DIPTERA SCOTICA: VI. THE WESTERN ISLES. 



By Percy H. Grimshaw, F.R.S.E., F.E.S. 



After a lapse of several years I am once more able to 

 resume my series of articles, commenced in the Annals of 

 Scottish Natural History, upon the Diptera of Scotland. 

 The area I propose to deal with in the present contribution 

 is practically untouched ground, for only sixteen species 

 appear to have been recorded hitherto from the islands off 

 our western coast. These records are contained in two 

 notes contributed to the Entomologist's MontJdy Magazine 

 by C. W. Dale in September 1882 and February 1884 

 respectively, and in a paper by Messrs A. E. J. Carter and 

 James Waterston, published in the Annals of Scottish 

 Natural History for April 1909. In order to render the 

 following list a complete record of what is known regarding 

 the Dipterous fauna of the Western Isles, I have included 

 these previous records and placed them in their proper 

 systematic position. 



In undertaking the compilation of this list, I have been 

 in the fortunate position of being able to examine an amount 

 of material which, I believe, represents the most complete 

 collection of Hebridean Diptera ever brought together. The 

 nucleus of this collection consists, in the first place, of a 

 fine series of specimens captured in various islands by 

 Mr Waterston ; and secondly, of the results of a trip 

 which I myself made to South Uist in the month of 

 June 1 9 10. My own material was obtained within a few 

 miles of Lochboisdale, and, since I was favoured with 

 exceptionally fine and sunny weather, and as I took care 

 to capture as many species as possible, if only for the sake 

 of record, the collection thus formed may be fairly regarded 

 as a representative one for that neighbourhood. My trip 

 was an official one, and all the specimens obtained are now 

 in the Royal Scottish Museum. 



In addition, I have been favoured with a few specimens 

 from Barra and Rum, collected by the Misses Baxter and 



