I will, however, give one curious and complex case, not indeed as affecting any important character, but from occurring in several species of the same genus, partly under domestication and partly under nature.  It is a case apparently of reversion.  The ass not rarely has very distinct transverse bars on its legs, like those on the legs of a zebra:  it has been asserted that these are plainest in the foal, and from inquiries which I have made, I believe this to be true.  It has also been asserted that the stripe on each shoulder is sometimes double.  The shoulder stripe is certainly very variable in length and outline.  A white ass, but not an albino, has been described without either spinal or shoulder-stripe; and these stripes are sometimes very obscure, or actually quite lost, in dark-coloured asses.  The koulan of Pallas is said to have been seen with a double shoulder-stripe.  The hemionus has no shoulder-stripe; but traces of it, as stated by Mr. Blyth and others, occasionally appear:  and I have been informed by Colonel Poole that the foals of this species are generally striped on the legs, and faintly on the shoulder.  The quagga, though so plainly barred like a zebra over the body, is without bars on the legs; but Dr. Gray has figured one specimen with very distinct zebra-like bars on the hocks.

With respect to the horse, I have collected cases in England of the spinal stripe in horses of the most distinct breeds, and of all colours; transverse bars on the legs are not rare in duns, mouse-duns, and in one instance in a chestnut:  a faint shoulder-stripe may sometimes be seen in duns, and I have seen a trace in a bay horse.  My son made a careful examination and sketch for me of a dun Belgian cart-horse with a double stripe on each shoulder and with leg-stripes; and a man, whom I can implicitly trust, has examined for me a small dun Welch pony with three short parallel stripes on each shoulder.

In the north-west part of India the Kattywar breed of horses is so generally striped, that, as I hear from Colonel Poole, who examined the breed for the Indian Government, a horse without stripes is not considered as purely-bred.  The spine is always striped; the legs are generally barred; and the shoulder-stripe, which is sometimes double and sometimes treble, is common; the side of the face, moreover, is sometimes striped.  The stripes are plainest in the foal; and sometimes quite disappear in old horses.  Colonel Poole has seen both gray and bay Kattywar horses striped when first foaled.  I have, also, reason to suspect, from information given me by Mr. W. W. Edwards, that with the English race-horse the spinal stripe is much commoner in the foal than in the full-grown animal.  Without here entering on further details, I may state that I have collected cases of leg and shoulder stripes in horses of very different breeds, in various countries from Britain to Eastern China; and from Norway in the north to the Malay Archipelago in the south.  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.