THE SKIN 305 



Grey legs, as apart from white, are usually only found in grey 

 horses. Grey horses may have grey legs or white legs. In 

 horses of any colour white coronets mean colourless feet, grey 

 coronets black feet, for the reason that the skin of grey horses is 

 pigmented. Black coronets yield a dark slate-coloured horn 

 commonly referred to as black. A coronet with black-and-white 

 markings yields a black-and-white striped foot corresponding to 

 the position of the markings on the coronet. If the coronet is 

 wholly white the hoof is without pigment ; it is frequently 

 spoken of as ' white,' but it is really yellow. White hair only 

 grows from a non-pigmented skin, and this condition constitutes 

 albinism, so that white coronets and yellow feet indicate local 

 albinism. Colourless feet are notoriously bad, and horses with 

 white legs are, in consequence, generally disliked. 



Face and Limb Markings. — Special attention has recently 

 been drawn to the face and limb patterns produced by white 

 hair in animals.* The face pattern may be symmetrical or 

 one-sided, may cover the whole front and side of the face, and even 

 involve the orbit. In this case the iris, sclerotic, and choroid 

 partake of the non-pigmented condition, showing that this is not 

 a mere accidental surface marking. Names have been given to 

 face markings, but these need not concern us. Too much white on 

 the face is a serious blemish, and a white muzzle with a pink 

 skin is objectionable. In the paper referred to the writer states 

 that the amount of white on the legs will be in ratio with the 

 amount of white on the face. If the ' star ' is not in the middle 

 line, he considers there will probably be a want of bilateral 

 symmetry in the markings of the limbs. He also points out that 

 the hind-legs are almost always more extensively involved than 

 the fore-legs, and that it is very rare to see white fore-legs only, 

 and the hind-legs escape. Hutchinson considers that, where 

 there is want of symmetry in the markings, as, for example, 

 the face-patch to one side, or two lateral legs white and their 

 fellows coloured, it may be suspected that the animal is not 

 developed with perfect bilateral symmetry in other respects. 

 He may be a ' left-handed ' horse, and if so, though strong and 

 efficient, will move awkwardly and be unpleasant to ride. We 

 do not share this latter view, but the whole matter is so interesting 

 and the facts so readily collected, that attention is drawn to 

 our ignorance of the question, and the necessity for observation. 



Albinism. — This is the absence of pigment from the skin, and 

 may be general or local. Local albinism commonly affects the 

 face and legs. It may be extremely local, as in wall-eyed horses, 

 who possess no pigment in the iris of one or both eyes. It may 



* ' On Paleogenetic Face-Pattern in Acroteric Piebalds.' Sir Jonathan 

 Hutchinson, F.R.C.S., F.R.S., British Medical Journal, June, 1910. 



