CHAPTER II 



CONTACTS WITH DARWINISM. 

 THE PODOSTEMACEAE 



i-T is not intended here to write a history of the movement known 

 as Darwinism, but rather to sketch the author's contacts with it, 

 which have lasted for fifty years. 



The pubh cation of the Origin of Species created a revolution in 

 the world of science, but like most great changes in ways of 

 thought it was very unwelcome to the older men, who rarely 

 came round so far as to accept it in any whole-hearted way. In 

 the next few vears there was a flood of ant i -Darwinian literature, 

 and many incisive criticisms were made upon natural selection 

 (rather than upon evolution) from one of which we quote the 

 next sentence: "It follows, therefore, that if we accept the 

 Evolutionists' view, every specialised chemical compound met 

 with in some living beings only must fulfil the condition, that 

 every approximation to the complete compound must have 

 been of advantage to the being in which it was produced in the 

 struggle for life. . .unless these very substances existed in, and 

 formed points of difference between, Mr Darwin's few original 

 forms" (29, p. 134). Maclaren also points out that change of 

 climate does not change the chemistry of a plant, so that there 

 is no opening for natural selection in a change of conditions. 



It was clear that there must be discontinuity in evolution, 

 and this was difficult to harmonise with the view that it had 

 proceeded by gradual accumulation of minute steps. Chemical 

 substances of differing nature could not be formed from one 

 another by slow and gradual steps, nor could gradual steps in the 

 formation of such a substance as the green colouring matter of 

 plants (chlorophyll), for example, be of value. Yet this, probably 

 one of the early formed organic substances, providing the food 

 for plants and animals alike, ranks with water and protoplasm 

 among the most important chemical substances in the world. 



The writer has been chiefly occupied with economic botany for 

 over forty years, and to him these considerations have long been 

 a fatal objection to the current theory of evolution — the gradual 

 passage, by reason of improving structural adaptation to the 

 surrounding conditions of life, from small variations through 



