Origin of Species Variorum

→ there is some evidence to render it probable, that 1859 1860 1861

there is a large body of facts rendering it probable, that 1866

OMIT 1869 1872

→ horns of almost full-grown 1859 1860 1861 1866

full-grown horns of 1869 1872

→ cattle. 1859 1860 1866 1869 1872

cattle. But further than this, variations which, for all that we can see, might have appeared earlier or later in life, tend to appear at a corresponding age in the offspring and parent. 1861

→ But further than this, 1859 1860 1866

I am far from meaning that this 1861

But 1869 1872

→ variations which, for all that we can see, might have appeared earlier or later in life, tend to appear at a corresponding age 1859 1860 1866

is invariably the case; and I could give a good many cases of variations (taking the word 1861

variations, which, for all that we can see might have appeared either earlier or later in life, likewise tend to appear at a corresponding age 1869

variations, which, for all that we can see might have first appeared either earlier or later in life, likewise tend to re-appear at a corresponding age 1872

→ offspring and 1859 1860 1866 1869 1872

largest sense) which have supervened at an earlier age in the child than in the 1861

→ a good many 1859 1860 1866

several exceptional 1869 1872

→ if their truth be admitted, will, 1859 1860 1861 1866

namely, that slight variations generally appear at a not very early period of life, and are inherited at a corresponding not early period, explain, as 1869 1872

→ and have probably 1859 1860 1861 1866

varieties, 1869 1872

→ race-horses 1859 1860 1861 1866

race-horses— breeds which have been almost wholly formed by selection under domestication— 1869 1872

→ and this surprised me greatly, as I think it probable that the difference between these two breeds has been wholly caused by selection under domestication; 1859 1860 1861 1866

OMIT 1869 1872

most of them, may have appeared at an extremely early period.

I have stated in the first chapter, that →there is some evidence to render it probable, that at whatever age

any

variation first appears in the parent, it tends to

re-appear

reappear

at a corresponding age in the offspring. Certain variations can only appear at corresponding

ages;

ages,

for instance, peculiarities in the caterpillar, cocoon, or imago states of the

silk-moth:

silk-moth;

or, again, in the →horns of almost full-grown →cattle. →But further than this, →variations which, for all that we can see, might have appeared earlier or later in life, tend to appear at a corresponding age in the →offspring and parent. I am far from meaning that this is invariably the

case,

case;

and I could give →a good many cases of variations (taking the word in the largest sense) which have supervened at an earlier age in the child than in the parent.

These two principles, →if their truth be admitted, will, I believe,

~~explain~~

explain

all the above specified leading facts in embryology. But first let us look

a few analogous cases in

our domestic

domestic

varieties. Some authors who have written on Dogs, maintain that the greyhound and

bull-dog,

bulldog,

though

~~appearing~~

appearing

so different, are really

varieties

~~varieties most~~

varieties most

closely

allied

allied,

→and have probably descended from the same wild stock; hence I was curious to see how far their puppies differed from each other: I was told by

breeder

breeders

that they differed just as much as their parents, and this, judging by the eye, seemed almost to be the case; but on actually measuring the old dogs and their

six-days-old

six-days old

puppies, I found that the puppies had not

acquired nearly

nearly acquired

their full amount of proportional difference. So, again, I was told that the foals of cart and →race-horses differed as much as the full-grown animals; →and this surprised me greatly, as I think it probable that the difference between these two breeds has been wholly caused by selection under domestication;