History of tlie Theory of Heredity. 49 



and xxviii.) is readily accessible, but it will not be out 

 of place to quote it before entering upon its critical dis- 

 cussion. 



lie says: '^In the previous chapters large classes of 

 facts, such as those bearing on bud-variation, the various 

 forms of inheritance, the causes and laws of variation, 

 have been discussed, and it is obvious that these subjects, 

 as well as the several modes of reiiroduction, stand in some 

 sort of relation to each other. I have been led, or 

 rather forced, to form a view, which to a certain extent 

 connects these facts by a tangible method. Every one 

 would wish to explain to himself, even in an imperfect 

 manner, how it is possible for a character possessed by 

 some remote ancestor suddenly to reaj^pear in the off- 

 si)ring; how the effects of increased use or disuse of a 

 limb can be transmitted to the child; how the male sex- 

 ual element can act not solely on the ovule, but occa- 

 sionally on the mother form; how a limb can be repro- 

 duced on the exact line of amputation, with neither 

 too much nor too little added; how the various forms of 

 reproduction are connected, and so forth. I am aware 

 that my view is merely a provisional hypothesis or spec- 

 ulation, but until a better one be advanced it may 

 be serviceable by bringing together a multitude of facts 

 which are at present left disconnected by any efficient 

 cause. As Whewell, the historian of the inductive 

 sciences, remarks, hypotheses may often be of service to 

 science, when they involve a certain loortion of incom- 

 pleteness or even of error. 



" Under this point of view I venture to advance the 

 hypothesis of pangenesis, which implies that the whole 

 organization, in the sense of every separate atom or unit, 

 reproduces itself. Ilence ovules and pollen grains — the 

 fertilized seed or ^gg, as well as buds — include and con- 



