22 PBOCEEDINGS OF THE 



to add that in these days it is not necessary to go to Germany to 

 find people " sneering out their souls " at adaptation ! It is a 

 curious habit of mind, but need not be taken too seriously. Such 

 justification as it has, lies in a pardonable reaction against the too 

 facile assumption of: hypothetical functions where direct evidence 

 was not available. That the great bulk, if not the whole, of 

 organic structure is of the nature of an adaptive mechanism or 

 device cannot be seriously doubted. 



The Origin of Species by means of Natural Selection does not, 

 as has sometimes been imagined, involve a constantly increasing 

 perfection of adaptation throughout the whole course of Evolution. 

 Darwin expressed his belief " that the period during ^^hich each 

 species underwent modification, though long as measured by years, 

 was probably short in comparison with that during which it 

 remained without undergoing any change."* 



During the long periods of rest, adaptation to the then existing 

 condition of life must have been relatively perfect, for otherwise 

 new variations would have had the advantage and change would 

 have ensued. It thus appears that, as a rule, a state of equili- 

 brium has existed in the relation of organisms to their environment, 

 only disturbed when the conditions were changing. That such 

 long periods of evolutionary stability have actually occurred is 

 shown, for example, not only by the familiar case of the Flora of 

 Egypt, unaltered during a long historic period, but still more 

 strikingly by the absence of any noticeable change in the plants 

 of our own part of Europe since glacial or pre-glacial times. 



The conclusion follows that at any given time, apart from the 

 relatively short critical periods when changed conditions had to be 

 met, we must expect to find organisms in a state of complete 

 adaptation to their surroundings. When physical and especially 

 mechanical conditions are in question, such as have practically 

 remained constant through all geological time, we may reckon on 

 finding the corresponding adaptive structures essentially the same 

 at the earliest periods as they are now. 



Hence, the attempt to support the Darwinian theory by the 

 detection of imperfect adaptations in Palaeozoic plants, is wholly 

 futile, as was well shown by the late Prof. Westermaier in a 

 controversy on this question a few years ago. Westermaier's 

 ovt'n point of view was not that of a Darwinian, but, never- 

 theless, his conviction that efficient adaptation has always been 

 characteristic of living organisms, is a perfectly sound one, 

 thoroughly in harmony both with the principles of Darwin and 

 Wallace, and with the observed facts, as far back at any rate as 

 the palaeontological record extends. In particular, Westermaier's 

 contention that the constru.ction of the Carboniferous plants 

 followed the laws of mechanical stability and economy of material, 

 just as is the case in plants of our own day, is completely con- 

 firmed by accurate observations on their structure, while his 

 opponent's supposed detection of palaeozoic constructions " in direct 



* ' Origin of Sjiecies,' 6th edition, d. 279. 



