We are not however limited to the womb as the only possible field of a pathogenic microbian growth. The frequent presence of microbes in the sphincter of the teat, in the galactophorous sinus, and in the milk ducts inside the mammæ is absolutely proved. Guillebeau found on the mucosa in cases of mammitis three forms of bacillus, to which he attributed the disease. In the New York State Veterinary College we have found mammitis usually associated with a streptococcus in the milk. In one cow in the University herd which gave abundance of good milk, and rarely showed any sign of congestion, streptococcus was constantly present. In cows producing “gassy” curd, V. A. Moore and A. R. Ward found in the milk a bacillus which morphologically and in cultures resembled the colon bacillus (evidently one of the colon group). In the milk and mammary gland tissue got from other (slaughtered) cows, a micrococcus growing in yellow or buff-colored colonies predominated. (Moore and Ward). That the colon bacillus, so constant in the intestines and manure, is not always found in the milk ducts, would show that in its normal condition it is not adapted to this habitat, but when a variety appears that is so fitted, it appears to be able to maintain its place indefinitely. With such facts before us, we must allow the possibility of poisoning by toxins of bacteria in the udder, or by compounds formed by the synthesis of such toxins and the leucomaines of the expanding udder, or by the union of the udder toxins with those from the womb. The whole subject of microbian and leucocytic causation of parturient fever is still hypothetical, yet enough is known to show the high probability of such source, and to demand a thorough investigation which will place the subject on a substantial and assured basis.