452 BRITISH LEPIDOPTERA. 



several miles, at an altitude of 2,000 ft. to 3,000 ft. They always 

 prefer the parts that are stony, and are rarely seen where the heather 

 grows freely. They are very sluggish in their habits. Reid says that the 

 insect is very rare on the mountain slopes where plant-life is luxuriant, 

 being almost confined to the lichen -covered wind-swept flats on the 

 mountain tops, and that, in its head-quarters, the food-plant grows in 

 small, dwarf, straggling patches among the stones and rocks. As we go 

 north the altitude at which it is found decreases, and Staudinger and 

 Wocke record that, at Bodo, on May 19th, 1860, the full-grown larvfe 

 were found on the marshes, which were only a few feet above the level 

 of the sea, and later at Alten, where it occurred not only on the 

 marshes, but also in quite dry pine-woods, and later on the high 

 mountains. As we go south, on the other hand, the altitude at which 

 it is found gradually increases, until in the central Alps it is rarely 

 found below 6,000 ft., and often reaches above 8,000 ft., or as high as 

 its food-plants can find sustenance. We have ourselves rarely found it 

 below 6,500 ft., whilst it appears to be more abundant at 7,000 ft. Fre- 

 quently at these levels it is to be observed in the utmost profusion. At Le 

 Lautaret, in August, 1896, we saw it in countless numbers, booming 

 everywhere on all the mountain slopes around. In dull weather the 

 moths hide at the roots of the plants that clothe the mountain sides, 

 but the slightest gleam of sunshine is sufficient to stir them into the 

 greatest activity. It appears to be fairly widely distributed in the 

 Braemar district, and probably has a greater range in the northern 

 Highlands than has yet been discovered. Hohenwarth captured the 

 type specimens of this species on the extreme Alpine summits of the 

 Gross Glockner, on the so-called Pasterze, and surmised that it lived 

 there on the " Eis-" or " iihrengetragenden Beifuss " (Artemisia 

 glacialisl), which are almost the only plants of this perpetual winter 

 land. 



Time of appearance. — Larvffi found July 2nd, 1851, in the Ober- 

 haslisthal, pupated July 5th-8th, emerged after 20 days from July 

 25th-28th (Freyer) ; often observed between July 26th-August 7th, at 

 Bossekop and Skaadavaara (Zetterstedt), first imago on June 26th, 

 1860, at Bodo (Staudinger), imagines abundant at Bossekop, from 

 July 9th to 20th, 1898 (Chapman), July 25th to August on the 

 highest summits of the Dovrefjeld mountains (Boheman), August 

 9th, 1851, on the Gemmi (Freyer), end of June, 1817, on the summit of 

 the Lozere (Duponchel), July 15th, 1897, on the Gemmi, just appearing 

 (Lowe), July 9th-16th, 1897, in Tosa Falls Valley (Bateson), July 17th, 

 1871, at 2,400-2,600 ft. (White), July 17th-25th, 1871, at Braemar 

 (Traill), July 10th-17th, 1886, at Braemar (Tugwell), at the end 

 of June and during the first half of July at Braemar (Home). In early 

 seasons it may be out in Scotland before the end of June. In Central 

 Europe in the Alps, at about 6,500 feet, it appears in the middle of 

 July, but keeps coming out at successively higher levels until the 

 middle of August. Chapman found it abundantly on August 20th, 

 1894, in the Grauson Valley (high above Cogne) in Piedmont, and 

 still later in 1895, at Oberalp (Switzerland). We found it well out 

 on the Mont Cenis Pass, August lst-5th, 1897, and on the Petit St. 

 Bernard, August 3rd-5th, 1898, at Le Lautaret and the Col du Gabbier, 

 August lst-8th, 1896, very abundant, August 10th-15th, 1895, on the 

 Falzarego Pass (above Cortina), August 8th-20th, 1894, in the Cogne, 



