10 4 NATURAL SCIENCE [August 



lutely alike, in consequence of their 'individual differences'; and 

 these supply material for natural selection to act upon. 



(3) That when a being migrates into a new environment, this 

 somehow induces variations to arise in the offspring, which then, it 

 is supposed, vary 'indefinitely,' i.e., in all sorts of directions; but 

 only those best suited to the new surroundings live, all the rest 

 die. Professor Huxley described this process of natural selection 

 of the fittest to survive, as a system of ' trial and error.' 



(4) That the rule is that plants of which there is a numerous 

 population are best suited for giving rise to new varieties when 

 some geological catastrophe alters the conditions of their existence, 

 i.e., without migration. 



(5) So that those individual plants which possess new varia- 

 tions of structure which render them the best fitted to survive, will 

 <lo so under those new conditions of existence. 



Now the statement No. 1 can be abundantly and easily proved 

 to be true. No. 2 is also quite true. No. 3 is not true so far as 

 varying ' indefinitely ' is concerned. This was an a priori assump- 

 i ion, which has never been verified, no facts having ever been brought 

 forward to sustain it. No. 4 is also unsupported by any facts ; on 

 the contrary, gregarious plants as a rule supply no varieties. No. 5 

 is a reasonable deduction or a priori assumption, had there been any 

 facts to start with. This not being the case the assumption falls to 

 the ground. 



On the other hand, observations and experiments prove that all 

 variations which arise in plants are the result directly or indirectly 

 •of responses or adaptations to external influences. Such are always 

 ' definite,' to use Darwin's expression, in every case ; and whenever 

 this is so, as he himself admits, " a new variety would arise without 

 the aid of Natural Selection." Instead of this being the exception 

 and indefinite variations the rule, as he supposed, the truth is, that 

 definite variation is a natural law admitting of no exceptions at all. 

 Indefinite variations in nature were a pure assumption. 



Where, then, is there any opportunity for natural selection to 

 act ? It is the universal process in the struggle for life in nature. 

 A neglected lawn, now existing, affords the writer an excellent object 

 lesson. Daisies hold their own over large areas where about four 

 years ago there were none ; but among them are sharply defined 

 places in which Poet annua or other grasses utterly refuse admis- 



to anything else. Another district is invaded by Alchcmilla 

 arvensis ; yet another consists of large plants of dwarf Dutch clover, 

 while Achillea millefolium, with its insidiously creeping stem, con- 

 stitutes a compact carpet; so does Galium verum in many places. 1 



1 In a lawn made on the side of a heath Galium saxatile formed the 'turf to an 

 almost entire exclusion of everything else. 



