27 
respect in each instance to some constant pair of differential cha¬ 
racters, e.fj., the crossing of a form in which the ripe seeds are always 
roundish in form and hardly wrinkled, with one in which they are 
angular and deeply wrinkled ; with the result that he found, in large 
numbers of trials, regular laws governing the ratios in the hybrids of 
the successive generations, and no blending at all of the differential 
characters, i.e., “ Transitional forms were not observed in any experi¬ 
ment.” Of each pair of characters investigated, one was found to be 
“ dominant,” i.e., to govern the appearance of the hybrid so essen¬ 
tially that the influence of the other character was not traceable ; but 
in the next generation (the progeny of the hybrids) the potency of 
this apparently lost character reasserted itself, giving in this genera¬ 
tion a definite ratio of dominant to non-dominant character of 8:1; 
and again, in the next generation, equally definite results followed, 
into which I cannot now enter in detail, the important factor being 
the regular splitting up of the progeny into hybrids (those which in 
their turn would yield progeny of both classes) and constants (those 
which, having reverted to a parental form, would thenceforth remain 
true to it). As Bateson says in his prefatory note, “ The conclusion 
which stands out as the chief result of Mendel’s admirable experi¬ 
ments is, of course, the proof that in respect of certain pairs of differen¬ 
tiating characters the germ-cells of a hybrid, or cross-bred, are pure, 
being carriers and transmitters of either the one character or the 
other, not both. ... In so far as Mendel’s law applies, therefore, 
the conclusion is forced upon us that a living organism is a complex 
of characters, of which some, at least, are dissociable, and are capable 
of being replaced by others. We thus reach the conception of unit- 
characters, which may be rearranged in the formation of the reproduc¬ 
tive cells. It is hardly too much to say that the experiments which 
led to this advance in knowledge are worthy to rank with those that 
laid the foundation of the “ Atomic laws of Chemistry.” 
