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412 method. The pine usually occurs pure; but in the ravines small and unimportant groups of silver fir are often seen, and the edges of the streams are bordered in many places by Alnus cordifolia. The beech in Corsica attains as high an elevation as Laricio, and in some cases the two species are mixed, and a struggle occurs for predominance. Birch is occasionally a component of the pine forest, but is comparatively rare. The soil on which Laricio grows is usually extremely poor, consisting of debris of granite rocks, and contains very little humus or decayed vegetable matter.

The following observations which were taken in 1906, at 3200 feet altitude, in the midst of the Laricio forest at Vizzavona, show the climate in which the tree thrives:—



Snow and low but not extreme temperatures are common during nearly six months of the year, from November to the beginning of May. The sky is generally clouded more or less completely during a greater part of the year; a clear blue sky only being recorded on 77 days out of the whole year.

The Laricio forests are easy of access, owing to the railway, which goes through the heart of the mountains from Ajaccio to Bastia; and in spite of a heavy fall of snow I succeeded in seeing some of the most important forests in the last week of December 1906. The finest is Valdoniello, which lies about twenty miles west of Corte railway station, the road to it passing through the magnificent gorge of the Scala di Santa-Regina. This forest occupies the upper basin of the river Golo, which has a north-easterly exposure, and its wooded area covers 6682 acres lying between 3100 and 5100 feet altitude. The soil is very dry and extremely poor, consisting of granite debris; and the few beech and silver fir that were seen could only obtain a footing in the ravines. The forest is divided into two series, one of which, about 4000 acres in extent is being regularly felled, whilst the other series at a greater elevation is left untouched as a zone of protection, In the first series