TYPHOID FEVER. 375 intestine, exists there in typhoid fever, and adds no little complication to the bacteriological diagnosis by respond- ing in exactly the same manner as the typhoid bacillus to the action of carbolic acid, by having colonies almost exactly like those of typhoid, by growing in exactly the same manner upon gelatin, agar-agar, and blood-serum, by clouding bouillon in the same way, by being of almost exactly the same shape and size, by having flagella, by being motile, and, in fact, by so many pronounced simi- larities as almost to warrant the assertion of some that it and the typhoid bacillus are identical. Not the least significant fact about the colon bacillus is that it is also pathogenic and capable of exciting acute inflammatory processes which are not infrequent, and which sometimes serve to increase the seriousness of typhoid fever. At the present time we are in more or less of a quan- dary about this extraordinary resemblance, but base our differentiation of the 3pecies upon certain constant, slight, but distinct differences. The typhoid bacillus does not produce indol. The open lymphatics and vessels of the intestinal ulcers of typhoid favor the absorption of the bacteria in the diges- tive tract, and the colon bacillus enters the blood no longer to be a saprophyte, but now to be a virulent pus- producer, and in many cases of typhoid we find suppura- tions and other milder inflammations due to this microbe. This is also a stumbling-block, for the typhoid bacillus when distributed through the blood may act in exactly the same manner. The typhoid bacillus may enter the body, at times, through dust (Klemperer and Levy), but no doubt, in the great majority of cases, enters the digestive tract at once through the mouth. It may possibly enter through the rectum at times, as illustrated by the mention which Eichhorst makes of the infection of soldiers in military barracks through the wearing of drawers previously worn bv comrades who had suffered from typhoid.