ADAPTATION 207 



3. Modification of the Colour of Salamandra maculosa induced 

 by Change in the Colour of the Soil on which the Animals were 

 kept. Kammerer speaks of this as the most convincing of all 

 his experiments on the transmission of acquired characters. So 

 far, however, no full account of them has been published. 21 The 

 statement is that when salamanders are kept in yellow surround- 

 ings the yellow markings gradually in the course of years increase 

 in amount relatively to the black ground colour. Conversely by 

 keeping the animals on black garden soil, the yellow may be 

 greatly diminished in quantity until it largely disappears. (The 

 account in Natur adds that very moist conditions also favour the 

 increase of yellow, and that with less moist conditions the yellow 

 diminishes.) From each kind, the (induced) yellower and the 

 (induced) blacker, a second generation was raised, on soil of 

 neutral colour, and each family was later divided into two parts, 

 half being put on black and half on yellow ground. 



As regards the offspring of those which had lived on black 

 soil no positive result had been reached up to the date of publica- 

 tion, but it is stated that these young resembled their parents 

 in having the yellow distributed in irregular spots. 



As regards the offspring of those which had lived on yellow 

 soil the account follows up the story of that part of the offspring 

 which were put on yellow soil again. It is stated that these, though 

 derived from parents with irregular spots, developed the yellow 

 as longitudinal bands. 



This account is given with slight differences of expression in 

 the three places to which I have referred. On returning from 

 Vienna in 1910 I consulted Mr. G. A. Boulenger in reference to 

 the subject, and he very kindly showed me the fine series from 

 many localities in the British Museum, and pointed out that in 

 nature the colour- varieties can be grouped into two distinct types, 



descriptive of the state of the larvae, which I have not attempted to represent, but 

 the account here given contains all that seemed essential to an understanding of 

 the more important features of the account. 



21 The first appeared in Natur, 1909-10, Heft 6, p. 94; and the second, which 

 contains coloured plates of the animals, in the lecture already referrred to, 12 

 Flugschr. d. Deut. Ges.f. Zilchtungkunde, Berlin, 1910, p. 26. In the paper in Mendel 

 Festschrift, 1911, the subject is continued, but no more is added as to this part of 

 the experiment. 



