November 25, 1910] 



SCIENCE 



747 



negligible except when we are dealing with 

 relatively small units. The geographer 

 will not neglect man ; he will merely be 

 careful to prevent himself from being un- 

 duly influenced by the human factor in 

 selecting his major units. 



Some geographers and many geologists 

 have suggested that land forms alone need 

 be taken into account in determining these 

 geographical units. Every different recog- 

 nizable land form is undoubtedly a geo- 

 graphical unit. A great mountain system, 

 such as that of western North America, or 

 a vast lowland, such as that which lies to 

 the east of the Eocky Mountains, is un- 

 doubtedly a geographical unit of great im- 

 portance, but its subdivisions are not 

 wholly orographieal. The shores of the 

 Gulf of Mexico can not be considered as 

 similar geographically to those of the 

 Arctic Ocean, even if they are morpholog- 

 ically homologous. I wish to laj^ great 

 stress on the significance of vegetation to 

 the geographer for the purposes of regional 

 classification. I do not wish to employ a 

 biological terminology nor to raise false 

 analogies between the individual organism 

 and the larger units of which it is a part, 

 but I think we should do well to consider 

 what may be called the life or movement 

 going on in our units as well as their form. 

 "We must consider the seasonal changes of 

 its atmospheric and of its water move- 

 ments, as well as the parts of the earth's 

 crust which they move over and even 

 slightly modify. For this purpose a study 

 of climatic regions is as necessary as a 

 study of morphological regions. The low- 

 lands of the Arctic area are very different 

 from those at or near the tropics. The 

 rhythm of their life is different, and this 

 difference is revealed in the differences of 

 vegetation. 



By vegetation I mean not the flora, the 

 historically related elements, but the veg- 



etable coating, the space-related elements. 

 Vegetation in this sense is a geographical 

 phenomenon of fundamental importance. 

 It indicates quality — quality of atmos- 

 phere and quality of soil. It is a visible 

 synthesis of the climatic and edaphic ele- 

 ments. Hence the vast lowlands of rela- 

 tively uniform land features are properly 

 divided into regions according to vegeta- 

 tion — tundra, pine forest, deciduous forest, 

 warm evergreen forest, steppe and scrub. 

 Such differences of vegetation are full of 

 significance even in mountainous areas. 



The search after geographical unity — 

 after general features common to recog- 

 nizable divisions of the earth's surface, the 

 analysis of these, their classification into 

 types, the comparisons between different 

 examples of the types — seem to me among 

 the first duties of a geographer. Two sets 

 of maps are essential — topographical and 

 vegetational — the first giving the super- 

 ficial topography and as far as possible its 

 surface irregularities, the latter indicating 

 quality of climate and soil. 



Much has been said in recent years — 

 more particularly from this presidential 

 chair — on the need for reliable topograph- 

 ical maps. "Without such maps no others 

 can be made. But when they are being 

 made it would be very easy to have a gen- 

 eral vegetational map compiled. Such 

 maps are even more fundamental than 

 geological maps, and thej^ can be con- 

 structed more rapidly and cheaply. Every 

 settled country, and more particularly 

 everj^ partially settled countrj-, will find 

 them invaluable if there is to be any intelli- 

 gent and systematic utilization of the 

 products of the count^}^ 



The geographer's task I am assuming is 

 to study environments, to examine the 

 forms and qualities of the earth's surface, 

 and to recognize, define and classify the 

 different kinds of natural units into which 



