CHAP. XXV 
PLATEAU-VENTS IN SCOTLAND 
395 
wholly or in part of dolerite, basalt, diabase, andesite, trachyte or other 
Fig. 123.— View of the two necks Dunigoyu and Duiiifoyii, Stirliug.sliire, taken from the south. 
These two necks form a conspicnnns feature in tout of and below the lava plateau, a portion of which is shown on 
the right hand. The ground-plan of the same necks is shown m lig. 124. 
crystalline rock, they present more irregular rocky outlines. Illustrations 
Fig. 124. -Ground-plan of Plateau-vents near Strathblane, Stirlingshire, on the scale of 
6 inches to a mile. 
of some of those varying forms are given in Figs. 23 and 123 
In rare 
