SUPPOSED TRANSMISSIOxM OF ACQUIRED CHARACTERS 397 



Supposed Transmission of Mutilations,' * no new observations 

 on this point have appeared. f The old arguments, on the 

 scientific worthlessness of which I then expressed my opinion, 

 are constantly being brought forward, — in part altered, and in 

 part with a new interpretation. It is now even less necessary 

 than ever to return to the matter, as even among those observers 

 who supported the view of the transmission of functional varia- 

 tions, a few agree with me in denying the transmission of 

 mutilations. As an instance, I may mention Osborn, who, 

 however, goes a little too far when he compares the contest of 

 the old view of the transmission of mutilations with Don 

 Quixote's celebrated fight with the windmills. J Only a few 

 years ago, at a meeting of the German association of naturalists,§ 

 two ' tailless ' cats were exhibited, in which the absence of the 

 tail was supposed to be due to their mother having accidentally 

 lost hers ; and biologists of such eminence as Ernst Haeckel || 

 have accounted for similar cases in the same way. Since such 

 men still regard the inheritance of mutilations as possible, the 

 exposition of the subject has not been a superfluous task.^f 



There is, however, a tliird kind of somatogeiiic variation, 

 produced by the influence of environment, the mode of nittrition, 

 the climate, and so on ; this often appears to be transmissible, 

 and consequently capable of becoming increased in the course 

 of generations. I myself called attention to this fact a number 

 of years ago in the following words : — 'I only know of one class 



* Jena, 1889, ' Essays upon Heredity, ' Oxford, 1889, p. 421. 



t None, that is to say, which are in opposition to my views. My experi- 

 ments with mice have been confirmed by Ritzema Bos and by Rosenthal. 

 I have now continued these experiments to the nineteenth generation — 

 always with the same negative results ; cutting off the tails has no influence 

 on the tails of the descendants. A similar result was obtained by both the 

 above-mentioned observers from experiments on rats {cf. ' Biolog. Central- 

 blatt," Vol. xi., 1891, p. 734, &c.). 



X Osborn, 'Are Acquired Variations Inherited? ' Boston, 1890, p. 3. 



\S At the meeting at Wiesbaden, 20th September 1887. 



II Haeckel, ' Xatiirliche Schopfungsgeschichte,' 3rd ed., 1889, p. 194. 

 English edition, ' The History of Creation,' London, 1876, Vol. i., p. 214. 



1[ See the Section on the Transmission of Mutilations in Eimer's book 

 entitled 'Die Entstehung der Arten,' Sec, Jena, 1888. (C/. 'Organic 

 Evolution as the Result of the Inheritance of Acquired Characters," &c., 

 translated by J. T. Cunningham, London, 1890.) A whole collection of 

 ' proofs ' are there given. 



