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SATYRWM. 
some, as E. Ligea and Euryale, have them chequered with grey and 
black. 
This generic group is well marked by the general colouring of 
the wings, and by the habit of the species. They are all inhabitants 
of regions which are more or less cold, generally on account of 
altitude, but sometimes of latitude, as in the case of Erehia Embla 
and Disa, which are found in Lapland. In countries which are 
quite flat or but little elevated above the sea-level the genus Erehia 
is entirely absent; it is poorly represented on islands, however 
large and mountainous they may be — England and Scotland, for 
example, though possessing considerable tracts of elevated country 
and by no means insignificant mountains, have at present only two 
species, E. JEthiops (the Scotch Argus) and E. Gassiope (the 
Mountain Einglet). In Ireland, though that island is mountainous 
in parts, Erehia is absent. Corsica, too, a large island situated 
comparatively near to the great central alpine ranges of Europe, 
which may be said to be the head-quarters of the genus, and itself 
possessing mountains on whose summits the snow often remains 
throughout the summer, does not number a single Erehia amongst 
its lepidopterous fauna. 
About sixty species are known, twenty-nine of which inhabit 
Europe ; others are found in Siberia, the Amur, the Himalayas, 
Arctic America, Colorado, Chili and Patagonia, several in South 
Africa, and one in Madagascar. Though some species occur in the 
plains and on the lower grounds, as E. JEthiops, Ligea, Medusa, &c., 
by far the greater number of the European species are found in 
mountainous regions at various elevations, as far as the verge of 
the unmelting snow. Many species only occur at particular 
elevations, so that the Erehice are more or less distributed in zones 
upon the sides of the mountains. The best plan, therefore, for 
those who wish to obtain a considerable number of species is to 
reside at some place having a certain elevation, and to work 
upwards and downwards from that station, thus saving the labour 
of makiug continual ascents in search of particular species. 
Zermatt and Chamounix are perhaps as good as any other places 
in Switzerland to choose for tliis purpose. All the species occur 
during the summer season, from the beginning of June to the end 
of August; those that inhabit mountain regions are single-brooded. 
