BOARMID^—BOARMIA. 215 



among heather or Vaccinium, or sometimes upon rocks. The 

 first mention of this strain of variation seems to be by Curtis, 

 who described it as a distinct species, under the name of 

 muralis, and said that it was found on walls in the Isle of 

 Arran. The most recent, and in some respects the most 

 striking, departure in this species made its appearance, so 

 far as is recorded, about the year 1887 in South Yorkshire, 

 where it was found by Mr. G. T. Porritt. In it the ground colour 

 is, as in other species in that district, black, sometimes deep 

 black, more frequently smoky-black ; in the extreme forms 

 the surface is almost smoothly black, with the nervures of a 

 deeper shade; in others the markings are faintly visible; again 

 in others a rippled white subterminal line is obscurely visible, 

 or else bright and conspicuous on both fore and hind wings ; 

 and again, others possess white clouds and streaks along the 

 area of the second line. With these are found intermediates 

 of every shade of smoky-brown and brown-black, with or 

 without the ordinary markings ; but, so far as I have seen, 

 melanism has not as yet progressed so far in this species as 

 to obliterate all the usual markings in more than a very small 

 proportion of the specimens ; neither does it seem to have 

 extended itself over the country. In the South -West of 

 Ireland a dull brown form is found in which the markings 

 are very strongly black, but the general range in that country 

 is as here — ordinary forms throughout the Southern districts 

 and well into the north, where gradually the grey form of 

 the Scottish Isles appears, but in the full ordinary size. A 

 curious variety, taken near Dublin by Professor Hart, is uni- 

 colorous dark smoky-brown, and bears a queer resemblance 

 to the dark form of the next species. In an interesting 

 specimen in the collection of the Rev. Joseph Greene the 

 very strongly rippled pale line of the hind wings and the 

 deep markings of the fore wings seen in the black Yorkshire 

 varieties are repeated in umbreous and light brown, and the 

 rippled line is nearly white. 



On the wing in June and July, sometimes even at the end 



