LÉPIDOPTEROLOGIE COMPARÉE 95 



lation, except that, in such cases, the apical spot of the fore wings 

 remains obsolescent. Coming further south the ochreous becomes 

 more tawny until it may assume the deeper hue of the Middle 

 Form, though occasional northern examples also are as strongly 

 coloured. On the under side, the Scotch laidion show a wide range 

 of variation; the apical spot of the fore wings sometimes distinct, 

 at others wholly wantmg; while the same may be said of the ante- 

 marginal ocellations of the hind wings, but as a rule thèse spots 

 are obsolescent, or even wholly wanting. Also the médian band is 

 generally eut short towards the centre and the continuation (as 

 m most southern examples) toward the anal angle wholly absent, 

 or inconspicuous. The greenish grey pamphiLus-\\\^Q ground colour 

 of the under side of the hnid wings présents a generally hirsute 

 appearance, thus affordmg the insect useful protection when at 

 rest on the stems of the beak rush and other marsh plants. The 

 tendency to local variations {inler se) is strongly marked, but on 

 the whole it is safe to conclude that the forms which hâve been 

 taken in Scotland in the laidion area approaching or appearing as 

 tiphon (type) or philoxenus are chiefly aberrations from the true 

 British Northern form. In the same way Middle Form examples 

 south of the Clyde-Knapdale line, which approximate to var. 

 laidion rather than tiphon may be regarded as local aberrations, 

 rather than constant geographical forms; though it is none the 

 less a fact, as I hâve already remarked, that areas exist where the 

 forms exist side by side. 



Tracing the distribution of Cœnonympha tiphon from its 

 extrême limits in the north and south of Scotland and the Isles, 

 the var. laidion, Bkh., fi.rst puts in an appearance in the Orkneys 

 from which group it is reported as scarce in Hoy, and resembling 

 the form of Central Scotland; and it must be something of a 

 rarity, for my correspondent Mr. Arthur Horne of Aberdeen, 

 tells me that al though he has collected there at the proper season 

 and although there are plenty of likely looking places, he has 

 never met with insular examples. There are, however, plenty of 

 Orcadian spécimens in our English cabinets of undoubted anthen- 



