OF SUTHERLAND AND CAITHNESS. 
61 
especially in the west and north-west, as a glance at a geological 
map will at once show ; and as we know that faunal characteristics 
in many other countries, as well as floral, are in a great measure 
dependent upon these, and upon one another, we desire to indicate 
the part which our subject counties bear in their natural as well 
as their artificial divisions and boundaries. Many indications of 
the importance and influence of these natural divisions are already 
within our grasp, but insufficient, perhaps, to warrant our occupy- 
ing more space than we have done in this place. 
Sutherland, West Cromarty, and Caithness are, therefore, com- 
posed of portions of three faunal areas: — 1st, West Eoss, which 
includes Skye and a part of Inverness, and which is marched on 
the south by Argyll, and on the east by the backbone of mountains 
which extends down the west side of Scotland; 2d, Sutherland, 
which in its entirety includes Caithness, and whose rivers run 
northward to the Atlantic Ocean ; and 3d, Moray, a vast faunal 
tract, whose basin is the Moray Firth, and whose catchment 
includes one-third part of Sutherlandshire and the larger portion 
of Inverness-shire, and jSTairn, Elgin, and Banff, and which is 
bounded on the south by the faunal areas of Argyll, Tay, and Dee, 
and on the east by Dee. 
