_Pathogenesis._ In Galtier’s first observations in Basses Alpes four separate flocks were infected by pigs brought all from one market, and placed in or by the pens of the sheep where they sickened and one in seven died in a few days. Then the mortality began among the sheep and ranged as follows: 1st flock lost 10 in 37: 2d flock 16 in 25: 3d flock 8 in 20: 4th flock 12 in 22. On one farm 10 sheep were sent to a neighbor’s just before the arrival of the sick pigs and escaped, and on another a second flock kept in outlying pens well apart from the home flock kept perfectly sound. With cultures of the microbe in vitro, he successfully inoculated sheep, goats, dogs, chickens, Guinea pigs, rabbits, and, finally, a calf and an ass. The cultures were inoculated in different cases; intravenously, into the trachea, pleura, lung, and subcutaneous connective tissue, and one goat was infected by ingestion. Lignieres claims that Galtier must have worked with a complex infection in which his (Lignieres’) cocco-bacillus was an essential constituent. The evidence of this is, however, lacking, and we must recognize that Galtier made cultures which showed the close relationship of his organisms to swine plague, and their lack of complete identity with those of the Lombriz. Lienaux and Conte had pathogenic results in a limited number of animals only (rabbit, mouse, Guinea pig) illustrating the familiar truth of the variability in the pathogenesis of different specimens of septicæmic bacteria of the colon group. _Symptoms._ 1. _Acute Form._ There is a sudden marked rise of temperature, often to 107° F., with acceleration of pulse and respiration. Sometimes death follows so early as to prevent the observation of other symptoms. If otherwise there supervene marked dulness, prostration, somnolence, anorexia, suspension of rumination, and more or less tympany of the rumen. The patient is found lying down, apart from the flock, indisposed to rise, with deep red, congested, arborescent conjunctiva and other mucous membranes, and petechial spots on these and on the white portions of the skin. The fæces, at first moderately firm and moulded in pellets, marked here and there with lines of mucus, or even blood, become on the second or third day soft, pultaceous, or watery and highly offensive. Parallel with this, emaciation advances with rapid strides. Breathing becomes more hurried, wheezing or snuffling, with a muco-serous, often bloody discharge from the nose, and an infrequent cough. Careful auscultation and percussion will often reveal the blowing or mucous râles, the crepitation or flatness on percussion of broncho-pneumonia. As the disease advances the petechiæ on skin and mucosæ extend, and extensive deep violet areas show especially on the inner sides of the arms and thighs, on the under surface of the tail, on the perineum and under the belly. Abortion is a common result, the lambs coming dead.