2 THE FOUNDATION OF ECOLOGY 



to formulate a system that will combine the good in each, and at the same 

 time eliminate superficial and extreme tendencies. In this connection, it 

 becomes necessary to point out to ecologist and physiologist alike that, 

 while they have been working on the confines of the same great field, each 

 must familiarize himself with the work and methods of the other, before his 

 preparation is complete. Both must broaden their horizons, and rearrange 

 their views. The ecologist is sadly in need of the more intimate and exact 

 methods of the physiologist: the latter must take his experiments into the 

 field, and must recognize more fully that function is but the middleman be- 

 tween habitat and plant. It seems probable that the final name for the whole 

 field will be physiology, although the term ecology has distinct advantages 

 of brevity and of meaning. In this event, however, it should be clearly 

 recognized that, although the name remains the same, the field has become 

 greatly broadened by new viewpoints and new methods. 



HISTORICAL DEVELOPMENT 



3. Geographical distribution. The systematic analysis of the great field 

 of -ecology is essential to its proper development in the future. A glance 

 at its history shows that, while a number of essential points of attack have 

 been discovered, only one or two of these have been organized, and that 

 there is still an almost entire lack of correlation and coordination between 

 these. The earliest and simplest development of the subject was concerned 

 with the distribution of plants. This was at first merely an off-shoot of 

 taxonomy, and, in spite of the work of Humboldt and Schouw, has per- 

 sisted in much of its primitive form to the present time, where it is repre- 

 sented by innumerable lists and catalogues. Geographical distribution was 

 grounded upon the species, a fact which early caused it to become stereo- 

 typed as a statistical study of little value. This tendency was emphasized 

 by the general practice of determining distribution for more or less arti- 

 ficial areas, and of instituting comparisons between regions or continents 

 too little known or too widely remote. The fixed character of the subject 

 is conclusively shown by the fact that it still persists in almost the original 

 form more than a half century after Grisebach pointed out that the forma- 

 tion was the real unit of vegetation, and hence of distribution. 



4. The plant formation. The corner-stone of ecology was laid by Grise- 

 bach in 1838 by his recognition of the plant formation as the fundamental 

 feature of vegetation. Earlier writers, notably Linne (1737, I75i)j Biberg 

 (1749), and Hedenberg (1754), had perceived this relation more or less 

 clearly, but failed to reduce it to a definite guiding principle. This was a 

 natural result of the dominance of descriptive botany in the i8th century, 



