1912-13.] BOTANICAL SOCIETY OF EDINBURGH 103 



feature of the geological structure is the intrusion of a 

 number of quartz-dolerite sills in the northern region of 

 the parish, these being prominent features of the landscape. 

 The dolerite varies much in structure, from a fine-grained 

 rock to one of a more coarsely granitic structure. 



There is much variation in the soil — from a stiff, almost 

 unworkable clay to a more easily worked and lighter sandy 

 or gravelly soil, sometimes mixed with peat earth. 



Peat covers large areas, making bleak the district where 

 it is dominant. In places it rests on glacial drift and 

 in others on the dolerite bosses. But where the rock 

 crops out, and where the coating of soil is consequently 

 thin, there is often an absence of peat, a feature which 

 is no doubt accounted for by the chemical composition 

 of the dolerite. 1 



Region of Cultivation. 



Of the total area of the parish something like 14.000 acres 

 are arable. It is a region which may be characterised as 

 " without wheat cultivation," there being only 2h acres of 

 wheat according to the latest returns. Oats are cultivated 

 all over, almost to the highest point of the parish. 



The following statistics from the Board of Agriculture 

 (see next page) give the chief subdivisions of the culti- 

 vated area and the comparison of these divisions for the 

 years 1867 (the year in which returns were first collected 

 on a basis similar to that of the subsequent years), 1902, 

 and 1912. 



One noticeable feature is the increase in permanent 

 grass, the returns for 1912 being 3082 acres and 244 acres 

 more than those for 1867 and 1902 respectively. There is 

 a decrease in the acreage under cereals as compared with 

 1867, and an increase as compared with 1902. 



Both with regard to position and to the character of the 

 soil oats cultivation is favoured. Owing to the altitude, 

 the unsheltered position of the land, and the amount of 

 rainfall, the parish does not lend itself to wheat raising. 

 In many places the country-side is bleak, the westerly winds 

 sweeping across it unhindered by mountain or hill. 



1 Cf. C. B. Crampton, " Stable and Migratory Plant Formations ; ' 

 (" Scot. Bot. Review," vol. L, No. 2). 



