1894. ^^^ ORIGIN OF SPECIES. 263 



regard to spinescent processes of desert plants ; but he again ignores 

 the primary argument of innumerable coincidences ; while in the case 

 of vegetative organs this argument has been in many cases " verified by 

 experiment." When, however, Mr. Wallace calls in question my 

 statement that spines are correlated with a dry soil and atmosphere, 

 he controverts those of Belt, Aitchison, Scott Elliott, Grisebach 

 and others, for he says : " There is no such general coincidence of 

 aridity of soil and atmosphere with abundance of spiny plants, as 

 very little enquiry will show." Having seen and gathered them myself 

 in the Libyan desert and even on our own sandy heaths, I cannot 

 accept this statement ; and if those eminent travellers I have named 

 are misleading us, where are we ? He then mentions the Galapagos 

 and other islands, where, though of a desert character, plants are not 

 spinescent. Here, again, I am not concerned with what does not 

 occur, but with what does. Moreover, any cause that may tend to 

 arrest an axis likewise may tend to render it spinescent, and more 

 than one cause may produce the same result, ^-^ so that it is not 

 altogether strange to find spinescent processes away from deserts ; 

 but I do maintain that spinescence is one and an important element 

 in the fades of hot and arid deserts with a barren soil. 



Mr. Wallace advances the well-worn theory of the interaction of 

 mammals and spines. In the first place, if I may still believe in the 

 prevalence of spines in deserts, they occur where no herbivorous 

 quadrupeds live. Secondly, if a mammal wishes to eat a spiny plant, 

 it somehow often gets over the difficulty ; thus donkeys knock off the 

 spines of Opuntia ; horses eat gorse. I had a cow which was partial 

 to holly, another rejoiced in nettles ! But all this is beside the 

 question. It seems to me that there is a lurking element of teleology 

 in this view : for any structure which arises in anticipation of its use 

 savours of natural theology^s rather than of evolution by natural pro- 

 cesses alone. I fully admit that plants, when once they have got 

 their spines, may be able to keep animals more or less at bay ; but 

 they originate, I maintain, as a mere accidental and inevitable result 

 of an arrest of the organ in question, ^uch arrest being mainly due to 

 drought. 



If teleology in its old dress of Design in anticipation of Use is, and 

 ought to be, extinct, we may accept Darwin's form of it, that Evolu- 

 tion is the Deity's method of creation. Let us, then, recognise proto- 

 plasm as having been impressed with the power of self-adaptation — 

 such being the inference from direct observation of its behaviour ; 

 and, consequently, enabled to build up structures in an automatic 

 response to the environmental forces, whenever it is necessary to 

 bring about a better degree of equilibrium between the internal and 

 external forces. 



" I observe Mr. Osborne makes a corresponding statement. Nat. Sci., p. 223. 

 15 Indeed, such anticipation is absolutely necessary for the theory of Natural 

 Selection in general. 



