102 THE POSITION OF THE [pt. ii 



On the other hand, to lay down, as the Darwinian evokitionist 

 does, that the order of development begins with the variety, 

 varieties diverging into species, species into genera, and genera 

 into families, is to reverse the method followed in nature, since 

 it imiDlies that the simpler, least mutable, and least adaptive 

 characters that distinguish the great families are the last de- 

 veloped. This could never have been. Nature has ever worked 

 from the simple to the complex, from the general to the par- 

 ticular. Had she followed the lines laid down by the Darwinian 

 school of evolutionists, there would be no systematic botany. 

 All would be confusion. There would be no distribution in the 

 sense in which the term is generally understood, and the plant 

 world would be a world of oddities and monstrosities. This is 

 the view expressed by the writer in his volume of West Indian 

 Observations published in 1917, p. 820 (47). 



It is this incompatibility between theory and practice that has 

 given Dr Willis his opportunity. Under the glamour of Darwin's 

 great theory Distributionists lost touch with old basic principles, 

 and it is as an endeavour to establish the old connections, or as 

 an effort to return to the pre-Darwinian position, which we have 

 largely abandoned or forgotten, that the Age and Area hypo- 

 thesis will find its place. The vain attempts to bring together 

 ends that could never meet, and the failures to reconcile views 

 that were hopelessly apart, have all prepared the way for a re- 

 consideration of the central problem of Plant-Distribution. 



Until we are in agreement about essentials we cannot utilise 

 the evolutionary standpoint for a general view of the subject. 

 The possible standpoints need much further exploration, and 

 several of the oldest have been forgotten. At any time a dis- 

 tributionist is liable to be held up by a query that in some quaint 

 old-time fashion will raise an issue that has been floating in 

 men's minds through the centuries. Distribution bristles with 

 the points made by the old philosophers, and many of our new 

 notions can there be matched. We cannot turn up any of the 

 old abandoned fields of research without unearthing some of 

 these old notions as fresh and as sound as in the days of their 

 entombment. But the query may belong more to our own time. 

 Thus one might be asked for the real significance of the fact that 

 Ave could found the Institutes of Botany on much the same 

 principles whether we based them on the flora of China or of 

 Peru. One of the implications of a recent paper by Dr Wilhs (135), 

 in which insular and continental floras are compared, is con- 



