On gray horses that at 10 or 12 years of age are turning white in color, purple-black malignant growths, known as pigment of melanotic tumors, frequently appear where the skin is black in color, and constitute the disease termed melanosis. The common seat of such tumors is the skin of the tail, anus, vulva, and lips, and while most often external, may be present internally. Such tumors are practically incurable, returning after having been amputated and cauterized. They usually burst and discharge bloody pus, and give the affected part a loathsome appearance. In young horses of gray color, a careful examination will often disclose small rudimentary tumors, and horses so affected should be bought with a right understanding of the consequences. Fatal attacks of a mysterious disease may be caused by internal melanotic tumors. As an indication of the probability of these tumors being present internally, the French veterinary scientists, Goubaux and Barrier, say in their “Exterior of the Horse”: “The hairs of the mane, like those of the tail, are ordinarily straight. One of our associates, Mercier, has communicated a remark on this subject, which was also believed by the Arabians: that it is in the white or gray horses with _frizzled_ or _curly_ hairs in which melanotic tumors are always found in the interior of the body, although none may have any apparent trace on the exterior, particularly under the tail and around the anus. This remark, the correctness of which we have verified a number of times, both on the living subject and in the cadaver, is very important, because of the dangers to which animals affected with melanosis are exposed.” [Illustration] Secrets of Buying and Selling Horses. Auction Sale Rules.[2] At the Chicago Stock-yards the auction sales of horses, conducted in the “Bull ring,” at Dexter Park, are regulated by certain definite rules which should be understood by horsemen and farmers. When a horse is brought in for sale a sign stating how the horse is to be sold is immediately exposed on the auctioneer’s rostrum. There are six of these signs, viz., (1) Sound. (2) Serviceably sound. (3) Wind and work. (4) Work only. (5) Legs go. (6) At the halter. Terms on all sales are strictly cash. All horses must be examined and tried by purchaser as soon as bought, and must be tried and accepted on the premises during the day of sale, as all guarantees on horses expire with that day, and on delivery of the horse. In no case can a horse be rejected except on the day of sale, unless sold as sound and proved to be a cribber, heavey, crampy or lame. If proven to have any of the four named faults, the purchaser shall have until 9 A. M. the following day to reject the horse. Purchasers failing to try and examine horses within the required time forfeit all right of rejecting them, and no horse sold to wind and work shall be rejected for any cause except he proves windy or will not work.