Among wild animals the skunk varies considerably in the amount of white on the body, and this too was found to be usually greatest on the left side.

A close examination of numerous striped or spotted species, as tigers, leopards, jaguars, zebras, etc., showed that the bilateral symmetry was not exact, although the general effect of the two sides was the same.

This is precisely what we should expect if the symmetry is not the result of a general law of the organisation, but has been, in part at least, produced and preserved for the useful purpose of recognition by the animal's fellows of the same species, and especially by the sexes and the young.

See _Proc.

of the Am.Ass.for Advancement of Science_, vol.
xxx.p.