Mendel's principles of heredity: A defence

The text of this e-book has mostly been preserved in its original form. One spelling error was corrected (considertion → consideration) and a few missing full stops inserted, bu...

But already many cases are known to which the rule in any simple form will not apply. Galton points out that it takes no account of individual prepotencies. There are, besides,...

But suppose that instead of individuals presenting one character in differing intensities, two individuals breed together distinguished by characters which we know to be mutuall...

_Dominance_, as we have seen, is merely a phenomenon incidental to specific cases, between which no other common property has yet been perceived. In the phenomena of _blended_ i...

[26] One species possesses a beautifully brownish-red coloured pod, which when ripening turns to violet and blue. Trials with this character were only begun last year. [Of these...

In order to facilitate study of the data in these experiments, the different characters of the seed plant will be indicated by _A_, _B_, _C_, those of the pollen plant by _a_, _...

This represents the average result of the self-fertilisation of the hybrids when two differentiating characters are united in them. In solitary flowers and in solitary plants, h...

We meet with an _essential difference_ in those hybrids which remain constant in their progeny and propagate themselves as truly as the pure species. According to Gärtner, to th...

2. With a single exception the hybrids in question form seeds capable of germination. _H. echioides_ ♀ x _H. aurantiacum_ ♂ may be described as fully fertile; _H. præaltum_ ♀ x...

Every case therefore which obeys the Mendelian principle is in direct contradiction to the proposition to which Professor Weldon’s school is committed, and it is natural that he...

The variations, or as I provisionally conceive it, that differentiant division among the gametes of which variation (neglecting environment) is the visible expression, has arise...

Bearing in mind, then, that the coats of peas may be transparent or opaque; and in the latter case may be variously pigmented, green, grey, reddish, purplish, etc.; that in any...

From this account who would not infer that we have here some mystery which does not accord with the Mendelian principles? As a matter of fact the case is dominance in a perfectl...

I have also noticed that a cross between a round white and a blue wrinkled pea will in the third and fourth generations (second and third years’ produce) at times bring forth bl...

[139] This is of course on account of the maternal seed characters. Unless the coat-characters are treated separately from the cotyledon-characters Laxton’s description is very...

But Professor Weldon cannot be warned. He told us the “law of dominance conspicuously fails for crosses between certain races.” Thence the start. I venture to give the steps in...

But in Mendelian cases we are concerned primarily not with the product of gametes of blended character, but with the consequences of the union of gametes already discontinuously...