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twin ocellated spots in sections 2 and 3 with a small fulvous ring 

 around, and the spot in section 4 reduced to a black point with a 

 narrow fulvous cincture, gives a very peculiar aspect to the specimens. 



The pattern of the hind-wings is arranged in exactly the same 

 fashion as that of the fore-wmgs, and the arrangement of the 

 nervures suggests a possibility of seven ocelli as in the fore-wings, 

 but with little probability of there being more than five owing to 

 the suppression of the first and seventh sections of the fulvous band, 

 5, 4, 3, 2, I, o are the number of ocelli (more or less developed) 

 that I can trace in my specimens, a perfectly black hind-wing 

 representing the latter number — o. 3 and 4 are the most common 

 numbers. It may be considered a very rare form in which the 

 ocelli of the hind wing reach 5, or in which they drop below 3. 

 The latter, however, happens more frequently than the former. 



I have spent so much time in analysing the variation of the upper 

 surface that I have altogether neglected what is of much greater 

 importance to the students of natural selection, the variation of the 

 under sides. Here we find a most complex colour development. 

 There is first of all a general sexual dimorphism strongly developed. 

 The males have the hind-wings a rich red brown, the females of a 

 paler tint. If we examine closely we see that the females have the 

 basal and outer areas of the fore-wings paler, and the fulvous band 

 brighter and more distinctly inclining to orange in colour. The 

 hind-wings may be divided into four sections, the basal area red- 

 brown in the males, sparingly scattered with grey scales, then a 

 red-brown transverse band, then a band more distinctly sprinkled 

 with grey than the basal area (this contains traces of the ocelli less 

 distinctly marked than on the upper wings), then an outer marginal 

 red-brown band. In my specimens the basal area is scarcely dis- 

 tinguishable from the red-brown band in contact with it. The 

 under sides of the males of the Val d'Ampezzo specimens are remark- 

 ably uniform, those from Mendel Pass, Bregenz, Rannoch, and (on 

 the whole) those from Coulport, have the bands well marked. 



The hind-wings of the females are divided into the same four- 

 banded areas, but the dark red-brown central marginal bands of the 

 male are distinctly paler and scattered with grey scales, whilst the 

 pale basal and ocellated bands become so sprinkled with grey as to 

 give them a very white appearance. In this direction the females 

 from Bregenz are most charming, the two pale areas being of a 

 lovely purple hue in many specimens. But the under-sides of the 

 hind- wings of the females present a distinct colour dimorphism 

 themselves. Instead of the form just described and which is of the 

 same type as the underside of the male, there is a form (and among 

 our Scotch specimens by far the most abundant form) in which the 

 basal and ocellated bands are of a distinct yellow ochreous hue. 

 When, as is sometimes the case, the ochreous bands present a 

 strong contrast to the red-brown areas, the result is most striking. 



It is true that in those fore-wings those spots which are in an ill- 



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