THE DISTRIBUTION OF INSECTS IN NEW HAMPSHIRE. 343 



tains, all comprised within a few square miles, exposed almost continu- 

 ously to the very fiercest gales ; they are covered by interminable broken 

 rock-masses, concealed in part by a scanty layer of mould, supporting 

 either sedges, or stunted juniper-like spruces, whose gnarled and spreading 

 branches creep along the ground. In Switzerland and the Tyrol these 

 regions extend over an area of thousands of square miles, more or less 

 continuous ; the highest mountains rise above them into the region of 

 perpetual snow, and form barriers to the wind, rendering the alpine slopes 

 scarcely more breezy than the plains. About the Belalp, above Brieg, 

 where I have paid most attention to the insects of the high Alps, the 

 trees seem to reach a general level of about 6000 feet ;* above them the 

 ground is sward, richly beautified by flowers, and a pasturing ground 

 for goats and cattle; on the slopes most exposed to the morning and 

 midday sun, immense patches of low, dark green shrubbery, seldom 

 rising more than a foot above the ground, dispute the soil with the grass. 

 These patches consist mainly of heather (Calluna) with Rhododendron and 

 several species of Vaccinium, and seem to represent the dwarfed spruces 

 of our alpine heights, which, near the forests, are also accompanied by 

 Vaccinium. The sward extends up to the snow and cliffs, and while 

 sedges are no doubt present, its mass is composed of Graminese. 

 During the few days early in July spent in this region, I noticed that 

 insects, especially butterflies, were most numerous between 5500 and 

 8000 feet above the sea. The most abundant species of the very highest 

 region were Pieris Callidice and Ercbia Manto ; and many caterpillars of 

 ]\IcIit(Ea Cynthia were found, crawling about the rocks. Between 6500 

 and 7500 feet, the more common species were Syriclitus vialvcE, (Eucis 

 Acllo (not rare), Bretithis Pales (common), two or three species of 

 Erebia, including E. Manto, Colias Palano (common), and Pieris Calli- 

 ^;V(? (common) ; Vanessa Atalanta a.nd Ag-/ais urtica; were also seen, the 

 latter frequently ; the species of CEneis and Brenthis seemed to occupy 

 an identical zone. Lower down, the Blues appeared in abundance, with 

 different species of Erebia ; Parnassius Apollo occurred in considerable 

 numbers, Syrichtns malvcs was extremely abundant, Aglais nrticcs was 

 very common, and eggs and young caterpillars could be found anywhere ; 



* Though the mountain slopes are often covered with large tracts of pasture land far below this, — a phenom- 

 enon unknown in the White Mountains. 



