LEPIDOPTEROLOGIE COMPARÉE lOI 



it would appear as though there were a mixed area, the Middle 

 Form tiphon as a fréquent aberration, but the Northern Form 

 laidion still in the ascendant. 



The late Mr. Herbert Goss, for so many years my colleague as 

 Secretary of the Entomological Society of London, took a few 

 laidion on the slopes of Ben Lawers (3984 ft.) ; and on a peat 

 bog at 1800 ft., some miles west of Killin, towards the south- 

 western end of Loch Tay. But in eastern and southern Perthshire, 

 that is to say in the lowlands, it is reported in his F mina Perthensis 

 to be rare by Dr. F. Buchanan White, one of the most diligent of 

 Scotch naturalists of the last génération. The only localities he 

 gîves are Moncrieff, and Methven Moss, a little to the north-west 

 of Perth; isis (meaning the extrême palest unocellated form) 

 accompanying it as an aberration. 



It may be assumed, then, I think, that, south of Aberdeen, in 

 the eastern counties north of the Forth, Forfai', Fife, and Kinross, 

 laidion has not been observed, supporting the view suggested by 

 Dr. Buchanan White that altitude to .some extent governs the 

 distribution of the form, though in the farther north as we hâve 

 seen, the butterfly comes down to sea level, as do also philoxenus 

 and tiphon elsewhere ! 



Examples from the north and central parts of Argyll, e. g. from 

 Oban, show but rarely a disposition to départ from the northern 

 form; and my own north-west Perthshire (Glen Lochay), and 

 north-west Stirling captures are still true laidion. In North 

 Knapdale, Argyllshire, at the base of the Cantire peninsula, 

 •Mr. A. Adie Dalglish (Entomologist, Vol. XXVIII, p. 278), 

 though silent on the subject of ocellation, describes the tiphon of 

 the district " the majority of a dark tawny colour, though some 

 are warmer in tone than others "; évidence corroborated to this 

 extent by Mr. John Mackay {loc. at., Vol. XIX, p. 54) who says 

 " the spécimens which I captured presented a great variety of 

 colour. Some of the spécimens were quite as dark as those taken 

 on tlie Yorkshire moors, while others were of the usual Scotch 

 form, almost white in colour ". So that, al this point, which 



