and the amount of the virulent saliva
introduced. Experiments have proved that the virus follows the course of
the nerves to the spinal cord and along the latter to the brain before the
symptoms appear. Gerlach, having collected the statistics from 133 cases,
has found this time, known as the period of incubation, to vary from 14 to
285 days. The great majority of cases, however, contract the disease in one
to three months after the bite has been inflicted.

_Symptoms._--As in dogs, both furious and dumb rabies are met with, the
former being more common in cattle. A sharp line of distinction, however,
can not be drawn between these two forms of the disease, as the furious
form usually merges into the dumb, from the paralysis which appears prior
to death. The typical cases of dumb rabies are those in which the paralysis
appears at the beginning of the attack and remains until death. The disease
first manifests itself by a loss of appetite and rumination, stopping of
the secretion of milk, great restlessness, anxiety, manifestation of fear,
and change in the disposition of the animal. This preliminary stage is
followed in a day or two by the stage of excitation, or madness, which is
indicated by increasing restlessness, loud roaring at times with a peculiar
change in the sound of the voice, violent butting with the horns and pawing
the ground with the feet, with an insane tendency to attack other animals,
although the desire to bite is not so marked in cattle as in the canine
race. A constant symptom is the increased secretion of saliva with a
consequent frothing at the mouth, or the secretion may hang from the lips
in long strings. Constipation is marked, and there is manifested a
continual, although unsuccessful, desire to defecate. Spasms of the muscles
in different parts of the body are also seen at intervals. About the fourth
day the animal usually becomes quieter and the walk is stiff, unsteady, and
swaying, showing that the final paralysis is coming on. This is called the
paralytic stage. The loss of flesh is extremely rapid, and even during the
short course of the disease the animal becomes exceedingly emaciated. The
temperature is never elevated, it usually remaining about normal or even
subnormal. Finally, there is complete paralysis of the hind quarters, the
animal being unable to rise, and but for irregular convulsive movements
lies in a comatose condition and dies usually from the fourth to the sixth
day after