ovals with downward-growing hair on the back part of the udder above the teats was observed and known in Massachusetts more than forty years age, and some of the old farmers of that day were accustomed to say that when these spots were large and well developed the cow would be a good milker. Guénon divided the milk-mirror into eight classes, and each class into eight orders, making in all no less than sixty-four divisions, which he afterwards increased by sub-divisions, making the whole system complicated in the extreme, especially as he professed to be able to judge with accuracy, by means of the milk-mirror, not only of the exact quantity a cow would give, but also the quality of the milk and the length of time it would continue. He tried to prove too much, and the consequence was that he was himself frequently at fault, notwithstanding his excellent knowledge of other general characteristics of milch cows, while others, of less knowledge, and far more liable to err in judgment, were inclined to view the whole system with distrust. My own attention was called to Guénon’s method of judging of cows some eight or ten years ago, and since that time I have examined many hundreds, with a view to ascertain the correctness of its main features, inquiring, at the same time, after the views and opinions of the best breeders and judges of stock, with regard to their experience and judgment of it merits; and the result of my observation has been, that cows with the most perfectly-developed milk-mirrors, or escutcheons, are, with rare exceptions, the best milkers of their breed, and that cows with small and slightly-developed mirrors are, in the majority of cases, bad milkers. I say the best milkers _of their breed_; for I do not believe that precisely the same sized and formed milk-mirrors on a Hereford or a Devon, and an Ayrshire or a native, will indicate anything like the same or equal milking properties. It will not do, in my opinion, to disregard the general and well-known characteristics of the breed, and rely wholly on the milk-mirror. But I think it may be safely said that, as a general rule the best-marked Hereford will turn out to be the best milker among the Herefords, all of which are poor milkers; the best-marked Devon the best among the Devons, and the best-marked Ayrshire the best among the Ayrshires; that is, it will not do to compare two animals of entirely distinct breeds, by the milk-mirrors alone, without regard to the fixed habits and education, so to speak, of the breed or family to which they belong.