_Immunization._ With valuable birds it may be desirable to secure immunization by non-fatal inoculations. Salmon secured this by first estimating the number of microbes in an mm. of the blood, then diluting until five drops would contain but one, or at most two of these organisms, and injecting this amount into the pectoral muscles. A sequestrum forms in the muscle and is gradually sloughed out, and the cavity heals, with resulting immunity. Pasteur produced a weakened virus by exposing the artificial bouillon cultures to air for from three to ten months, the strength decreasing with the length of exposure. The weaker form produces slight illness only, from which recovery is prompt. A second and stronger virus is used ten or twelve days later and produces a real immunity. The drawbacks to these methods are: 1st; that fowls are of too little value, to warrant inoculation in healthy flocks; 2d; that in infected flocks, where it is employed, the more susceptible birds are usually already contaminated, and a large proportion die in spite of it; and 3d; that it becomes a means of planting the infection in new localities (Kitt). _Treatment._ The disease is so deadly that little can be hoped from medicinal treatment. It has been directed mainly to gastric and intestinal disinfection. Copperas and sulphuric or hydrochloric acid in the drinking water ½ to 1 per cent. of each is at once prophylactic and curative. Friedberger and Fröhner add fennel or peppermint, and give a tablespoonful every hour to an affected chicken. Other agents recommended are: carbolic acid (5:100) by the mouth or subcutem (Nocard), salicylate of soda, quinia (Cadeac), tannic acid (2:100), salol, naphthol, tar water, etc. DISTEMPER IN DOGS AND CATS.