THE 



EITOMOLOaiST'S 

 MONTHLY MAGAZINE: 



VOLUME L VI U. 



[THIRD SEEIES, VOL. VIII.] 



ON THE OCCASIONAL OCCUREENCE OF BUTTERFLIES IN ICELAND; 

 WITH NOTES ON THE LEPIDOPTEROUS FAUNA OF THE NORTH 

 ATLANTIC ISLANDS. 



BY JAMES J. WALKEE, M.A., R.N., F.L.S. 



The question as to the occurrence of any indigenous species of 

 Bhopalocei'a in Iceland has for a long time formed a subject of discus- 

 sion with those entomologists who are interested in the geographical 

 distribution of insects. At first sight it would appear highlj- improbable 

 that an island considerably larger than Ireland, Ijang within the influence 

 of the Gulf Stream and thus possessing a climate much less severe than 

 that due to its high latitude, can be entirely destitute of butterflies, 

 several species of which are well known to extend their range to the 

 northernmost limits of land. But all available evidence hitherto appears 

 to show that no really native butterfly is found in Iceland, with j^ossibly 

 one exception to be referred to hereafter ; and that most, if not all, the 

 butterflies that have been observed within its limits are wanderers from 

 more genial regions which have successfully braved the dangers of the 

 stormy North Atlantic Ocean. 



It is true that a great part of the interior of Iceland is altogether 

 vmsuited to insect life, consisting as it does of ice-covered mountain 

 slopes, extensive fields of naked lava, and vast stretches of loose volcanic 

 sand, all equally destitvite of vegetation of any kind. Many parts of the 

 island, however, especially in the north, are comparatively fertile and 

 luxm'iant, and can even boast of what may be called miniature forests 

 of sallow, willow, and birch, the latter tree sometimes attaining a height 

 of twenty feet or more. The Icelandic flora, too, is fairly rich, as, 

 according to Dr. Lauder Lindsay (Edinburgh New Philos. Journal, 

 new series, vol. xiv, pp. 64-101), it comprises no fewer than 426 species 



B 



