( cvii ) 



The word centrifugal suggests characters developing from 

 within rather than as impressed from without : centrijyetal 

 conversely suggests characters impressed upon the individual 

 from without, characters which are not the outcome of internal 

 causes.* Acquired structural changes have also been spoken 

 of as modifications, the term variation being i-estricted to char- 

 acters of germinal origin, f 



All the terms suggested for these two classes of characters 

 convey something of a definition. Thus the brief convenient 

 definition of acquired characters as " those modifications of 

 bodily structure or habit which are impressed on the organism 

 in the course of individual life " | is obviously suggested more 

 or less completely by one set of terms, and " those characters 

 or properties with which the individual is originally endowed" § 

 by the other set. Another attempted definition of an acquired 

 character is as follows : — " Whenever an organism reacts under 

 an external force, that part of the reaction which is directly due 

 to the force is an acquired character." || And although it may 

 be impossible entirely to unravel the one part from the other, 

 certain elements may easily be discriminated. For instance, 

 the starting of the reaction as contrasted with the sequence of 

 events which make up the reaction itself is obviously an 

 acquired element, and those who maintain the hereditary trans- 

 mission of acquired characters are required to prove that a 

 reaction which can only be started by an external force in the 

 parent, starts without this stimulus in the offspring. 



We owe another definition to Mr. Francis Gal ton : — " Char- 

 acters are said to be acquired, when they are regularly found 

 in those individuals only, who have been subjected to certain 

 special and abnormal conditions."* * 



Professor Lloyd Morgan's definition conveys nearly the 

 same idea : — -" When the complex of stimuli, which constitute 

 the normal environment, are sufl&ciently altered (to upset that 



* "Theories of Heredity," in the " Midland Naturalist," Nov. 1889. 



t Prof. J. Mark Baldwin, "A New Factor in Evohition," in the 

 "American Naturalist" for July 1896. 



X Professor C. Lloyd Morgan in Baldwin's " Dictionary of Philosophy 

 and Psychology," New York, 1901, vol. i, p. 10. 



§ E. S. Goodrich, I.e., p. 10. 



II "Nature," vol. li, 1894, p. 55. 



* * Ibid., p. 56. 



