INTRODUCTION 



Finally, I succeeded, through the facts 1 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 ^ 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.^ 

 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 w^ho 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 ou the Variation of the Wall-Lizard : a Contribution to the 

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

 f. Xaturrjeschichte, Berlin, 1881. 



^ In the zoological Jahreshericht 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. Tliis 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 Natitr for seller and in the Pi^evue der Naturwissenschaften. But K. Diising has 

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

 of Kosmos of 1886. 



