410 THE JOURNAL OF BOTANY 
he gives a full account, arranged chronologically “as a record 
of botanical investigation in the county.” He has based his 
botanical divisions ‘‘ upon the surface geology of the county so far 
as practicable”’: this, of course, is scientific, but a glance at the 
geological map shows its practical inconvenience; the millstone 
grit, for example, runs through the county from north to south, 
in the introductory chapter on ‘ Soils and Species’’; other chapters 
on ‘Climate and Species” and ‘“ County Rainfall” (the latter by 
Dr. H. R. Mill, Director of the British Rainfall Organization), with 
a very interesting summary, showing the constitution of the Flora 
according to Watson’s “ types of distribution,” complete the intro- 
ductory matter. 
