appears granular, and unequally stained in its different parts. It may be difficult of discovery in old standing lesions of horses, but comes out clearly in recent lesions of experimental cases in Guinea pigs and donkeys. Baumgarten claims sporulation but this is uncertain. The bacillus has only limited power of resistance to destructive physical and chemical agents. It is killed in 10 minutes at 55° C., in 2 minutes at 100° C., or by mercuric chloride solution (1:5000), or by phenol (5:100), or by permanganate of potass (1:100). In warm dry air and sunshine it is sterilized, in thick layers in 2 months (Peuch), in moderate layers in 4 to 15 days (Galtier), and in very thin layers in 3 days (Cadeac and Malet). In moist, cool air and in the shade it is much more resistant. In stables it may remain virulent for three or four months, and thus the disease has often reappeared among the newly introduced horses after a stable has been abandoned for a length of time. The microbe does not grow in infusions of hay, straw or horse manure, and it is doubtful if it can maintain an active saprophytic existence. Its vitality and virulence, however, persists in putrefying materials for 14 to 24 days, and in water from 15 to 20 days. Hence it is largely propagated through drinking troughs and occasionally through ponds, lakes and sluggish streams. Again the virus is likely to be preserved in and transmitted by rotten or even sound woodwork, as of mangers, racks, buckets, shafts and poles, and by harness, halters, blankets, combs, brushes and rubbers. Sometimes direct transmission takes place in snorting or coughing, or by the animals biting or licking each other. As the virus is spattered on surrounding objects, the walls, stable utensils, soiled fodder and feed, and even the attendant’s clothes may be the medium of transmission. Contagion during copulation is not unknown, nor infection of the fœtus _in utero_ from a diseased mother. Carnivora (dog, cat, lion) fed on the diseased carcasses have become infected. Experimentally infection has been conveyed by administering, by the mouth, balls containing the virus (Renault, Coleman, etc.), and again by transfusing the blood from a bad case of glanders into the veins of a sound horse (Viborg, Coleman, Renault, Hering, Chauveau, Nocard). Transmission through the air on dust is counteracted by the speedy destruction of virulence on dust, and horses often stand side by side in adjacent stalls for months without communicating the infection. Such escapes may, however, in some of these cases, be attributed to the immunity secured by a previous exposure and slight attack. That the germs may be exceptionally conveyed through the air appears to have been proved by Viborg and Gerlach, who collected the floating dust in a stable containing infected animals and successfully inoculated with it.