VIEWS OF G ALTON AND WEISMANN 169 



acquired characters were transmitted. On Weismann's view 

 the sole fountain of specific change is in the germ-plasm of the 

 sex-cells. It is true that the environment makes dints on the 

 organism, but only upon its body ; the reproductive cells, 

 through which alone the change could be transmitted, are 

 either unaffected or are not affected in such a definite way as to 

 bring about the transmission of the parental modification. It is 

 true that the results of changed function (use and disuse) are often 

 very marked, and very important for the individual; but they 

 are not transmitted as such or in any representative degree, and 

 therefore are of no direct account in the evolution of the species. 

 Thus the ground is taken from under the feet of Buffonians and 

 Lamarckians, and the whole burden of organic progress is laid 

 upon germinal variation and the processes of selection. 



The following sentences indicate Weismann's original posi- 

 tion: 



(1) "Acquired characters are those which result from external 

 influence upon the organism, in contrast to such as spring 

 from the constitution of the germ." 



(2) " Characters can only be inherited in so far as their rudiments 

 (' Anlagen ') are already given in the germ-plasm." 



(3) " Modifications which are wrought upon the formed body, 

 in consequence of external influences, must remain limited 

 to the organism in which they arose." 



(4) " So must it be with mutilations, and with the results of use 

 or disuse of parts of the body." 



(5) " No such modifications of the soma (affected by environment 

 or by use and disuse) can be transmitted to the germ-cells, 

 from which the next generation springs. They are, there- 

 fore, of no account in the transformation of the species." 



(6) "The only principle that remains for the explanation of the 

 transformation of the species is direct germinal variation." 



On germinal variations natural selection operates in the 

 usual way. The helpful subsidiary theory of germinal selection 

 was afterwards suggested, and various saving clauses were added, 

 which do not, however, affect the clearness and strength of 

 Weismann's original position. 



