VERTICAL Distribution of rhopalocera in the alps. 325 



as soon as we ascend to the pine woods many other species com- 

 mence to occur, especially of the group closely allied to E. epi- 

 phroii, wliile others continue to exist up to the line of congelation, 

 among the latter being E. lappona, E. tyndarus, E. gorge, and 

 E. glaciaUs, the abundance of some of them giving the upper alpine 

 zone quite a distinctive character of its own. Of the typical 

 genus Satyrus the three most familiar species are perhaps Satyrus 

 hermione, S. semele, and S. cordula, which are all more or less 

 plentiful in certain localities, but do not, I think, ascend beyond 

 the upper limits of the belt of deciduous trees, namely, about 

 4000 it. Pararge mara and P. hiera, however, occur among the 

 conifers, in company with P. ageria var. egerides and P. megara. 

 Epinephele ianira and E. hyperantlies swarm everywhere up to 

 the elevation of 8000 to 4000 ft. 



The little Coenonympha pamphilus does not appear to be very 

 abundant in the Alps, although it occurs up to an altitude of 

 about 6000 ft. Its place seems to be occupied by a closely allied 

 species, namely, C. satyrion, which occurs in great plenty in the 

 pine woods in certain localities, and even extends its area of 

 distribution to the upper alpine zone. C. arcania, of which the 

 preceding is supposed by some authorities to be merely a moun- 

 tain variety, reigns supreme at lower elevations. 



The Hesperiidse are comparatively numerous in species in the 

 Alps; all the British species of this family, with the solitary 

 exception of Hesperia acUeon, I have found more or less commonly 

 up to the region of the conifers. A large handsome species, 

 Spilothyriis lavaterce, occurs, but only singly, on the lower slopes 

 of the mountains up to about 4000 ft., in company with several 

 species of the genus Syrichthus closely allied to our own S. malva, 

 while S. alvens I have seen at an elevation of over 8000 ft. in 

 several parts of the alpine range. 



The preceding is by no means a complete list of the Rhopa- 

 locera which are found in the Alps, and is only intended to 

 furnish an account of the more familiar forms which occur at the 

 various altitudes, and which may be met with almost every season 

 by every one who cares to undertake a trip into the region in 

 question. 



Now, in order to intelligently study the vertical distribution of 

 the Rhopalocera in the Alps, it is necessary to adopt a series of 

 vertical or ascending zones. These supply a much more conve* 

 nient means of tabulating their occurrence at the various eleva- 

 tions than mere absolute altitude above the sea-level, as the 

 climatic and phanerogamic conditions vary so much in different 

 parts of the range, often on account of purely local circumstances, 

 that figures are frequently very misleading. As the result of my 

 own independent observations, I have been enabled to propose the 

 series of vertical zones given on page 827. They are practically 

 the same, however, as those defined by Messrs. Speyer in their 



