90 



moment. The number depended not upon the will of the experimen- 

 tist and was not subjected to a change e. g. increase in this moment. 



But those animals had the advantage ofbeing descended from 

 only one mother and therefore, the number of ex,)erimental factors 

 particularly of heredity was diminished and the analysis of experi- 

 ment simplified. 



Supposing, we had a large number of animals in this experi- 

 ment, they are descended from several females, so we had the 

 number of experimental factors doubled, trebled and still more 

 augmented. 



In the case of my experiment, the influence o parental factors 

 is limited to the least posible number and therefore a great niany factors 

 become eliminited. The experiment only gained in exactitude. 



Moreover, Prof. Werner overlooks the following note of mine : 

 — „D'e Versuche waren in der Biologisehen Versuchsanstalt in Wien, 

 wo sie auch fortgesetzt und be stättigt wurden, ausgeführt." 

 I made this Statement on the basis of a verbal message of the Di- 

 rector Zool. -Department, Prof. H. Przibram and 1 had no ground 

 for not believing it then and I still believe it. 



From this declaration, I conclude, that later a larger number 

 of individuals was experimented on and the res u It was the same. 



I do not know, whether this confirming experiments were 

 anywhere published or not. 



Ad. 2. The objection, that the time (duration) of the experi- 

 ment was too Short, is without foundation, because the influ- 

 ence by means of experiment, that is to say the sphere 

 of time-influence was limited only to such a Short 

 time. The Intention of the experiment was to influence the change 

 of colours during the^larval period but not, after the me- 

 tamorphosis. 



I had not reason to prolonge the experiment and I could pro- 

 longe the larval period. If 1 intended to prolonge the experiment, 

 I should not write about the colours of Salamandras, whose larvae 

 were reared in yellow and black environment but 1 should speak 

 of the colours of the Salamandra's, whose larvae had been reared 

 even during the larvae period in yellow and black environment. 



1 hope, Prof. Werner will understand the difference between 

 these two experimental purposes. 



The drawing of the Salamandras were made immediately after 

 the metamorphosis and if we look carefuily at the figures, we can 

 still observe some remaining characters from the larval period, for 

 instance in fig. 3 the shape of the head and of the tail. 



Besides, 1 say expressly (p. 343.): „Alle diese Farbenanpas- 

 sungen sind Wirkungen des Untergrundes auf die Larven. Die 

 Larvencharaktere kann man noch an allen Versuchs- 

 tieren an der Schwanzform erkennen. Diese wurden nach 

 der Verwandlung sofort, wie sie sich an das Landleben zu gewöhnen 

 begannen, gezeichnet". 



In conseqnence of inattentive reading of my treatise, Prof. 

 Werner reached false conclusions and made inaccurate Statements. 



