“In the first class he places cows, both parts of whose milk-mirror, the mammary and the perinean, are large, continuous, uniform, covering at least a great part of the perineum, the udder, the inner surface of the thighs, and extending more or less out upon the legs with no interruptions, or, if any, small ones, oval in form, and situated on the posterior face of the udder. Cows of this class are very rare. They give, even when small in size, from ten to fourteen quarts per day, and the largest size from eighteen to twenty-six quarts a day, and even more. They continue in milk for a long period. “The second class is that of good cows, and to this belong the best commonly found in the market. They have the mammary part of the milk-mirror well developed, but the perinean part contracted or wholly wanting. Small cows of this class give from seven to ten or eleven quarts a day, and the largest from thirteen to seventeen quarts. “The third class consists of middling cows. When the milk-mirror really presents only the lower or mammary part slightly developed or indented, and the perinean part contracted, narrow, and irregular, the cows are middling. Cows of this class, according to size, give from three or four to ten quarts per day. “The fourth class is composed of bad cows. No veins are to be seen either on the perineum or the udder, while those of the belly are very slightly developed, and the mirrors are ordinarily small. These cows give only a few quarts of milk a day, and dry up a short time after calving. “Mr. C. L. Flint, in his work on ‘Milch Cows,’ says:— “These classifications, adopted by Pabst, Magne, and others, appear to be far more simple and satisfactory than the more complicated classification of Guenon. Without pretending to judge with accuracy of the quantity, the quality, or the duration which a particular size or form of the mirror will indicate, they give to Guenon the full credit of his important discovery, as a new and valuable element in forming our judgment of the milking qualities of a cow, and simply assert, with respect to the duration of the flow of milk, that the mirror that indicates the greatest quantity will also indicate the longest duration.