_Incubation_ in inoculated cases varies from four to seven days (Krajewski). When contracted by simple exposure it may seem to have been extended to fourteen or even eighteen days. _Symptoms._ The _earliest symptom_ is hyperthermia (103° to 104° F.) This is accompanied and followed by prostration, dulness, impaired appetite, erection of the hairs along the spine, shivering, trembling, seeking a warm place, fatigue on slight exertion, hot dry nose, burning pads of the feet, sometimes taciturnity. Later the temperature may descend even to the normal or there may be alternations of rise and fall. One of the most characteristic symptoms of distemper is the implication of more than one set of organs, so that morbid manifestations referable to the nose, eyes, throat, stomach, skin and nervous system occurring in the same subject are to be especially noted. In enumerating the prominent symptoms caused by disease of one set of organs therefore, it is not to be implied that the absence of others referring to a different class of organs is to be understood. On the contrary a complication of several is especially significant of this disease, though the predominance in one class of organ will signify a special form of the disease. _Respiratory Symptoms._ One of the earliest symptoms is usually sneezing with redness of the nasal mucosa, followed by a muco-purulent blocking of the nose, and rubbing of it with the paws. With the implication of the throat there is usually local tenderness and a hard, painful cough, which may be accompanied by retching or vomiting. The breathing becomes snuffling, especially in pugs and bull dogs, and rapid and even oppressed in case of implication of the smaller bronchia and lungs. The nostrils may become glued together, the discharge red or dark in color, vesicles and sores may appear on the mucosa, and the cough gets paroxysmal, small, weak and husky or gurgling.