Dr. Gilchrist on some rare Alpine Plants. 313 



The following papers were read : — 



1 . " Account of a Botanical Excursion to the Braemar Mountains 

 in August 1854," by Prof. Balfour. 



The Professor gave an interesting account of his tour with his 

 pupils and friends, and mentioned the localities of several plants ob- 

 served. 



2. " Report on the Diatomacese collected in Braemar in the 

 autumn of 1854, by Prof. Balfour and Mr. G. Lawson,'* by Dr. 

 Greville. (See page* 252.) 



3. " On the Geological Relations of some rare Alpine Plants," by 

 Dr. Gilchrist. 



Oxytropis campestris is a plant confined to a single isolated lo- 

 cality in Clova. It grows on a cliff facing the south, which is some- 

 what isolated from the surrounding rocks by two perpendicular in- 

 dentations, which, as they are the result of weathering, indicate some 

 change in the structure or composition of the rocks. That on which 

 the plant grows, and to which it is limited, is a micaceous schist, 

 extremely rich in mica, of a dark colour, and rapidly undergoing 

 decomposition. The immediately surrounding rocks are of the same 

 general character ; but the mica is greatly less in proportion to the 

 other materials, and lighter in colour. 



Lychnis alpina is confined to a few isolated localities. It grows 

 on the summit of a hill called Little Gilrannoch, at about equal di- 

 stances from Glens Isla and. Dole. It seems limited to about half an 

 acre of surface. The rock is a tabular mass of compound felspar, 

 apparently capable of resisting decomposition. While in many places 

 it is bare and flag-like, other portions of it present a singularly rough 

 and irregular surface, as if the rocks had undergone fusion previous 

 to expulsion, small portions of it bearing a distinct resemblance to 

 similar specimens from the so-called " vitrified forts." The relations 

 of this plant to the rock on which it grows are well seen, many of 

 the specimens growing in little crevices of the bare rock, where there 

 is not the slightest vestige of soil, ordinarily so called. The rock, co- 

 extensive with the limits of the plant, is unvaried in character. Its 

 relations to those around could not be ascertained. 



Astragalus alpinus grows upon the summit of Craigindal, a hill 

 about 3000 feet in height. To the east of Braemar we gathered 

 specimens of this elegant little plant, in two separate localities, at a 

 considerable distance from each other, but the rocks on which both 

 grew were the same, a very pure compact felspar, of which the entire 

 hill seems to be formed. 



4. *' Descriptions of new Coniferous Trees from California," by 

 Mr. A. Murraw. 



The descriptions were rather horticultural than botanical, and 

 botanists must wait for some accurate and scientific definitions of 

 them, before they can be admitted as described species. 



