ALLEN ON GEOGRAPHICAL DISTRIBUTION OF MAMMALS. 377 



The relation of the difterent primary regions and their subdivions 

 may be approximately indicated diagrammatically as follows : — 



II. 



d 



III. 



V. 



/ b 



a 



2 i 1 



I 



3 



a 



Ob 



\ d 



a 



Dm 



II. 



IV. 



a I 



h I 3 



VI. 



Bull. iv. No. 2 5 



