INTRODUCTION 



Finally, I succeeded, through the facts I established, in 

 referring the separation into species, of which neither Darwin 

 nor any of his successors had given a satisfactory explana- 

 tion, in connection with the rest of my views, to natural 

 causes. 



I have expounded these views at full length in a second 

 paper l on the variation of the wall-lizard. 



But it seemed that very few investigators in the province 

 of the doctrine of evolution troubled themselves about the 

 wall-lizard, or about facts obtained from such a common 

 animal, or about the conclusions to be drawn from them. It 

 is possible, indeed, that the title of my papers was not very 

 inviting. I ought to have put Darwinism first, and the wall- 

 lizard second. Possibly the latter might then have been 

 honoured too possibly, for the tendency of the " scientific " 

 zoology of to-day is to neglect the study of entire animals. 2 

 Anything that is not teased with the needle, or cut with the 

 microtome, or examined with the microscope, is scarcely 

 noticed at the present day, except by those who are exclusively 

 systematists, even in questions connected with the evolution 

 theory. For, strange to say, even the doctrine of evolution is 

 left entirely in Germany to the decision of anatomy and em- 

 bryology, that is, of the microscope, or else is given up to mere 

 speculation, although Darwin himself, the reviver of this doc- 

 trine, used neither the former nor the latter, but external 



1 " Researches on the Variation of the Wall-Lizard : a Contribution to the 

 Theory of Evolution from Constitutional Causes, and also to Darwinism." Arch. 

 /. Naturgeschichte, Berlin, 1881. 



2 In the zoological Jahresbericht of the Zoological Station in Naples for 1881, 

 published 1883, p. 219, I read: "Th. Eimer has published a very important 

 paper, well worth reading, on the variation of the wall-lizard. This comprehen- 

 sive memoir is not of a kind to be briefly summarised, and therefore the reader is 

 referred to the original." That is all the favourable acknowledgment of the 

 memoirs in question which I have read up to quite recently, excepting reports in 

 the Naturforscher and in the Revue der Natunoissenschaften. But K. Busing has 

 just published a report showing complete comprehension of my meaning in vol. ii. 

 of Kosmos of 1886. 



