384) is that of the fleshy appendages on the corners of the jaw of Normandy pigs and of some other breeds.

But it is expressly stated that they are not constant; they appear "frequently," or "occasionally," they are "not strictly inherited, for they occur or fail in animals of the same litter;" and they are not always symmetrical, sometimes appearing on one side of the face alone.
Now whatever may be the cause or explanation of these anomalous appendages they cannot be classed with "specific characters," the most essential features of which are, that they _are_ symmetrical, that they _are_ inherited, and that they _are_ constant.

Admitting that this peculiar appendage is (as Mr.Romanes says rather confidently, "we happen to know it to be") wholly useless and meaningless, the fact would be rather an argument against specific characters being also meaningless, because the latter never have the characteristics which this particular variation possesses.
These useless or non-adaptive characters are, apparently, of the same nature as the "sports" that arise in our domestic productions, but which, as Mr.Darwin says, without the aid of selection would soon disappear; while some of them may be correlations with other characters which are or have been useful.

Some of these correlations are very curious.

Mr.Tegetmeier informed Mr.Darwin that the young of white, yellow, or dun-coloured pigeons are born almost naked, whereas other coloured pigeons are born well clothed with down.