218 THE ENTOMOLOGIST. 



NOTES ON THE LEPIDOPTERA OF THE OUTER 



HEBRIDES. 



By J. Jknxer Weir, F.L.S., F.Z.S. 



The thanks of all entomologists are due to Mr. E. G. Meek 

 for his further additions to our knowledge of the Lepidoptera of 

 the remote islands of Scotland. Mr. Meek has had a collector at 

 Lewis for thirteen weeks during the past season, and he has 

 returned to London with a most interesting series of insular 

 varieties. The collection was made at Stornoway, or within a 

 radius of twenty miles of that port. The collection, although 

 valuable and instructive, is not quite so interesting as that 

 Mr. Meek had from the Shetlands last year. 



The Outer Hebrides lie about 2° south of the Shetlands, 

 and 5° further west. The geological formation of the two 

 groups is similar. The bulk of the Shetlands consists of gneiss 

 rocks and granite; nearly the whole of the Outer Hebrides 

 are of the same formation. In the peninsula of Eye, near 

 Stornoway, granite obtains. Both groups are naturally treeless, 

 but extensive plantations have been made near the castle, at Stor- 

 noway, and with the imported trees some of the insects captured 

 have been introduced into the district. The Island of Lewis, in 

 which the collection was made, with the exception of the Eye 

 Peninsula adverted to, is a mass of grey gneiss rocks, with poor 

 soil, and large proportions of peat and moor. The peat bogs 

 are covered with Myrica gale and an abundance of Osmunda 

 r eg alls. 



Upon first examining the Hebridian collection one is struck 

 by the fact that they present no resemblance to the Shetlandic, 

 and that, especially amongst the Geometrte, the prevailing colour 

 is grey. 



The Shetlands are far more distant from the mainland 

 of Scotland than the Hebrides. The isolation being greater in 

 the former isles, the differentiation of species into local varieties 

 has been more complete, probably in i-esponse to their environ- 

 ment, and also because immigrants from Scotland must be very 

 rare, and a variety once localised would not be interfered with by 

 crossing with the ordinary type. The Hebrides have certainly 

 had the coloration of the Geometrse and other moths, which rest 



