388 NATURAL SCIENCE. June, 



variations, due to growth and' development of each individual 

 specimen, with perfect indifference, year after year, and in every one 

 of the numerous localities where marsh-marigolds grow ; and it makes 

 no effort to see if it can select any particular form which might possibly 

 be able to start on a new evolutionary career. For, no variety has ever 

 arisen in England in low-lying situations. 



When, however, this plant manages to get away from its habitual 

 environment and to reach " mountainous places " (Hooker), it puts on 

 characters which descriptive botanists have independently noticed and 

 variously named as varietal or specific. 7 It is commonly known as 

 Caltha minor. 



These two kinds, or the highland and lowland forms of Caltha 

 palustris, would, therefore, seem to illustrate Mr. Wallace's two terms 

 " definite or adaptive " and " developmental or non-specific " 

 characters respectively ; only he has omitted to mention, as I said 

 above, the " indefinite" characters of the majority of individuals, out 

 of which Natural Selection is supposed to have selected the " definite " 

 form known as Caltha minor. The fact is, there is no evidence what- 

 ever that they ever did exist. Caltha minor illustrates Darwin's 

 assertion about the " definite action " of an environment, namely, 

 that under such, " a new sub-variety would be produced without the 

 aid of Natural Selection." 8 



But, let us not forget that what is true for Caltha is, of course, 

 true for all other plants. It may stand as a type of the origin of all 

 true varieties of plants, or " incipient species," as Darwin calls them. 

 In other words, of the primeval seeds of Caltha palustris, which 

 happened to be transferred from lowlands to mountainous places, all 

 that survived grew up in direct adaptation to the new alpine environ- 

 ment, and so formed the so-called species Caltha minor, " without the 

 aid of Natural Selection." But this change could never have occurred 

 without the physiological self-adaptibility with which living proto- 

 plasm is endowed. It is here, therefore, as I take it, that the writer 

 in Natural Science very rightly insists upon the sine qua non of 

 " function " being taken into account when " the question of species 

 and of changes in them are to be dealt with " (p. 219). " The question 

 as to whether such small dimensions [as observed by Professor 

 Weldon] have, or do not have, a selection-value for the animal remains 

 to be answered " (p. 220.) My reply is that under usual conditions 

 of growth and development, in plants at least, they have no selection- 

 value at all. 



The Note adds : " Professor Weldon's method concerns itself 

 merely with the fact that in certain cases there is a relation between 

 selective destruction and certain specified dimensions." Is the word 

 " destruction " the right word to use ? The crabs measured, however 

 abnormal, were all alive and well, and of the same age. I would 



7 See Hooker's " Students' Flora of the British Islands," p. 11. 

 s " Animals and Plants under Domestication," ii., pp. 171, 279. 



