Popular Science Monthly/Volume 45/August 1894/Correspondence

CORRESPONDENCE.
 

"WEISMANN'S CONCESSIONS."

Editor Popular Science Monthly:

Dear Sir: In your issue of this month is an article by Prof. Lester F. Ward entitled Weismann's Concessions. In this Prof. Ward endeavors to show that Prof. Weismann has virtually acknowledged his own hypothesis on the inheritance of acquired characters to be untenable. But Prof. Ward's reasoning is vitiated by a thread of error that runs through the whole article, viz., the assumption that, in showing that Weismann concedes modification of the germ-plasm by agencies outside itself, with consequent variety in inheritance, he has shown that Weismann concedes the "inheritance of acquired characters" in the sense in which this expression is used by Weismann, Romanes, Lankester, and most other biologists of note. By the expression "inheritance of acquired characters," as used by Weismann and Romanes, is meant the acquirement de novo of characters by the somatoplasm of an individual (not characters that the somatoplasm has acquired in consequence of a modification of the germ-plasm) which, in some way, so modify that individual's germ-plasm that its descendants inherit the characters that it originally acquired. This is obviously very different from a modification of the germ-plasm by agencies external to it, that causes the development of new characters in the individuals developed from this germ-plasm and in their descendants. This last is not inconsistent with Weismann's theory of the continuity of the germ-plasm, while the "inheritance of acquired characters" (in the sense used by Weismann) is. Prof. Ward also speaks of the Lamarckian law as if he thought what is generally meant by "Lamarckianism" was different from "inheritance of acquired characters" (in Weismann's sense). He makes another obvious mistake where he criticises Weismann's statement on the inheritance of syphilis, and, if my memory serves me, he makes a great deal more out of his quotation from Romanes than Prof. Romanes ever meant, or the context of the words quoted justifies.

Weismann, while one of the clearest reasoners among biologists, is at times a little hard to understand on account of his style, and I think if Prof. Ward will reread his works he will see that he has not done Prof. Weismann justice.

I do not mean to pose as a supporter of all Weismann's views, but he seems to me to have a clearer conception of the problem of inheritance of acquired characters and of the nature of the proof necessary to solve it than almost any other man. At the same time there is hardly an author who is more misquoted and misrepresented—he is one of Darwin's chief rivals in this respect.

Yours very truly,F. R. Welsh.
328 Chestnut Street, Philadelphia,
June 9, 1894.