In all parts of the world these stripes occur far oftenest in duns and mouse-duns; by the term dun a large range of colour is included, from one between brown and black to a close approach to cream colour.
I am aware that Colonel Hamilton Smith, who has written on this subject, believes that the several breeds of the horse are descended from several aboriginal species, one of which, the dun, was striped; and that the above-described appearances are all due to ancient crosses with the dun stock.

But this view may be safely rejected, for it is highly improbable that the heavy Belgian cart-horse, Welsh ponies, Norwegian cobs, the lanky Kattywar race, etc., inhabiting the most distant parts of the world, should have all have been crossed with one supposed aboriginal stock.
Now let us turn to the effects of crossing the several species of the horse genus.

Rollin asserts that the common mule from the ass and horse is particularly apt to have bars on its legs; according to Mr.Gosse, in certain parts of the United States, about nine out of ten mules have striped legs.

I once saw a mule with its legs so much striped that any one might have thought that it was a hybrid zebra; and Mr.W.C.

Martin, in his excellent treatise on the horse, has given a figure of a similar mule.