Reviews and Book Notices. 



127 



limit reaches 2,500 feet. The moorland zones of vegetation 

 are: (i) a lower zone of grass heath and heather associations 

 covering the Sidlaw-Ochil ranges, and again represented on the 

 foothills of the Grampians north of Strathmore ; {2) an extensive 

 Grampian zone of heather moors, on fairly uniform schistose 

 formations ; (3) a higher zone of grassy moors on a geological 

 area of disturbed and contorted strata ; (4) an Arctic region 

 with an altitude of from 2,500 to 3,500 feet on the plateau 



Birch Wood in Glen CSova, looking up the South Esk. 



(Reproduced by permission from photo by Frank Sharp, Esq., Dundee.) 



between Strathmore and the Dee valley. The higher zone of 

 grassy moors is an extensive tract which in Yorkshire is only 

 found as a summit pasture on Great Whernside, Ingleborough, 

 Crossfell, and other hills. The Arctic region includes the classic 

 botanical localities of Clova and Caenlochan. Along the North 

 Sea coast, maritime vegetation is well represented in clifts, sand 



1905 April I, 



