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JOURNAL OF VARIATION. 



Vol. XXI. No. 1. January 15th, 1909. 



The Lepidoptera of the Orisons — The Sertig=Thal. 



By J. W. TUTT, F.E.S. 

 The morning of August, 5th, 1908, broke doubtfully at Davos ; large 

 heavy clouds hang over the valley, whilst others collected round the 

 highest peaks and presaged rain. However, the sun shone brightly be- 

 tween the cloudy intervals, and a start was made for the Sertig-Thal. 

 Across the valley to Claradel, where more " baths " and " open-air beds ' ' are 

 to be found, and one finds oneself in the Sertig-Thal. This is a much 

 narrower valley than the Dischma-Thal, but almost as highly cultivated, 

 although, as it ascends more steeply, the cultivated patches are more 

 quickly left behind. The abundance of Odezia [Tanaijra) atrata {ehaero- 

 /i/ijjllata) was most marked; the 5 s principally rested on the grass and 

 other plants in the meadows, but thcc? s were on the wing flying in the sun 

 everywhere. It was, however, a most unusual sight to me to see them 

 busily feeding on the flowers of wild thyme. On the little wild-thyme 

 patches by the edges of the meadows or on the top of the stone-walls, 

 they collected, resting on the flowers with extended and quivering- 

 wings, their probosces dug deep into the nectaries of the florets, ever 

 changing their position as they fluttered round a thyme head, 

 successively probing each floret in turn, and then passing on to another, 

 their white-tipped black wings continually vibrating up and down and 

 looking very fresh and fine in the sunlight, and theirantennfe extended 

 in front ; but they remained when the sun was hidden ; on two or three 

 occasions also examples were noticed on the horse-droppings in the 

 road, from which they seemed to be extracting some moisture. 

 Arfujnnh aijlaia and A. niohe flew joyously up and down the slopes, 

 whilst, on every small piece of waste ground, Adkinia coprodactyla was, 

 as in all these neighbouring valleys, readily disturbed. A few 

 examples of Aricia astrarche and Polyonuuatus icariis were also 

 noticed, whilst Melampias melanqm^ flew almost everywhere, nor was 

 there any diminution in the abundance of Ficris brassicae, which, in all 

 the valleys of this part of the Grisons this year, amounted to a veritable 

 plague. Hundreds were often in view at one time, half-a-dozen 

 alwaj's, even when cloudy or rain was slightly falling. The shadow 

 of two large butterflies (and the specimens were large) would fall in 

 front of one, and a 5 would be observed flying steadily, and a J^ a foot 

 or so from her, now above, now behind her, fluttering down to her, 

 and forcing her at last nearer and nearer to the ground. Presently 

 she would settle, and he would follow with quivering wings and take 



