It may be remarked, at the outset, that the fact that the best of the signs of a great and good milker adopted by Guénon are generally found united with the best forms and marks almost universally admitted and practised upon by good judges, gives, at least, some plausibility to the system, while the importance of it, if it be correct, is sufficient to demand a careful examination. Every good judge of a milch cow, for instance, wants to see in her a small, fine head, with short and yellowish horns; a soft, delicate, and close coat of hair; a skin soft and flexible over the rump; broad, well-spread ribs, covered with a loose skin of medium thickness; a broad chest; a long, slender tail; straight hind legs; a large, regularly-formed udder, covered with short, close, silky hair; four teats of equal size and length, set wide apart; large, projecting lacteal veins, which run along under the belly from the udder towards the fore legs, forming a fork at the end, and finally losing themselves in a round cavity; and when these points, or any considerable number of them, are found united in a cow, she would be pronounced a good milker. An animal in which these signs are found would rarely fail of having a good “milk-mirror,” or _escutcheon_; on which Guénon, after many years of careful observation and experiment, came to lay particular stress; and on the basis of which he built up a system or theory so complicated as to be of little practical value compared with what it might have been had he seen fit to simplify it so as to bring it within the easy comprehension of the farmer. As one means of forming a judgment of the milking qualities, however, it must be regarded as very important, since it is unquestionably sustained by facts in a very large majority of cases. The milk-mirror, or escutcheon, is formed by the hair above the udder, extending upwards between the thighs, growing in an opposite direction from that of other parts of the body. In well-formed mirrors, found only in cows which have the arteries which supply the milky glands large and fully developed, it ordinarily begins between the four teats in the middle, and ascends to the vulva, and sometimes even higher, the hair growing upwards. The direction of the hair is subordinate to that of the arteries; for the relation existing between the direction of the hair above the udder and the activity of the milky glands is apparent on a careful examination of all the cases. When the lower part of the mirror is large and broad, with the hair growing from below upwards, and extending well out on the thighs, it indicates that the arteries which supply the milky glands, and which are situated just behind it, are large and capable of conveying much blood, and of giving great activity to the functions of secretion.