Lcpidoptcra of the Altai Mountains. 343 



of maurisius, with the outer margin of the hind-wing below 

 resembling that of theano. Such a specimen, however, 

 does not exist in the large series which I took, but 

 even if it were theano, I prefer to retain the name now 

 generally known for the species' here described and 

 figured. First as to their habitat : maurisius is an alpine 

 butterfly occurring in greatest numbers from about 7000 

 to 6000 feet on wet grassy and rocky hill-sides, above and 

 within the limits of the larch woods. In the Bashkaus 

 Valley I took it as low down as 5000 feet, and here, as 

 well as at Kuyuktana, between Kurai and the Upper Tchuja 

 Steppe, I found it in company with theano, and though 

 some specimens are so like theano that when taking them 

 I did not distinguish them, there are none which I cannot 

 now assign with tolerable certainty to one or other species. 

 Maurisius was first taken on July 15th near Darkoti in the 

 mountains south of the Tchuja Steppe, and became very 

 abundant about a week later, when I took the first 

 females. At Kuyuktana on July 22nd and 23rd the 

 males were getting somewhat worn, whilst the males of 

 theano were quite fresh and the females not yet out. On 

 the pass between Kurai and the Bashkaus it was so 

 abundant at from 6000 — 7000 feet that I got twenty 

 females in one day, and as I descended this valley it was 

 gradually replaced by theano, and disappeared altogether 

 before I descended to the Tchulishman Valley. 



The range of theano in this district therefore appears to 

 be from about 3000 — 6000 feet, and that of maurisius 

 from 5000 to nearly 8000 feet. The latter varies extremely, 

 as will be seen by the figures I give ; but the characters 

 by which it may be invariably distinguished from theano 

 are as follows. On the underside the band of fulvous 

 elongated blotches on the fore-wing below are evenly 

 bounded on the inside by the darker chocolate of the cell, 

 whilst in theano the fourth and fifth spots, which are 

 normally longer and paler than those of maurisius, are 

 longer inwardly than the third spot. In theano the group 

 of spots at base of hind-wings below is far better defined 

 and more developed, though they are sometimes nearly 

 wanting, and in the females of maurisius are sometimes 

 present, though never to the same extent as in theano. The 

 outer margin of fore- and hind-wings below is normally 

 grey in theano,* whereas in maurisius it is of the same 

 * In figure 5 the colour comes out too red. 



