224 ON POULTRY LOUSINESS IN THE HORSE. 
itching, causing them to rub themselves incessantly and without 
relaxation; so that we observe upon the skin, in those places 
the most rubbed, lesions, which we may call traumatic , con- 
sequent on the violent action occasioned by the bodies against 
which the animal rubs himself. These epidermic excoriations 
appear either in series of lines or in broad patches, or in places 
irregularly circumscribed, according to the regions in which they 
are found, and the nature of the bodies against which the friction 
has taken place. They are principally remarkable upon the 
lateral parts of the head and neck, upon the back and croup, 
upon the sides and flanks, and upon the internal parts of the 
limbs. They look either very angry or bloody when observed 
immediately after the rubbing, or they are covered with red 
incrustations more or less adherent, according to the length of 
time they have existed ; or else they appear in a state of granu- 
lation and suppuration, whenever the skin has become suffi- 
ciently deeply injured. But these superficial lesions of the skin 
do not by right belong more properly to poultry lousiness than 
to any other pruriginous disease ; and, so far from being con- 
sidered as one of their peculiar features, we ought to look upon 
them as simulating those affections to which they in truth be- 
long, and which they stand in the place of. 
This disease in no way interferes with the integrity of the 
general functions. Apart from the violent excitement the 
animal may experience, and the consecutive irregularity of his 
respiration ^ind circulation it may occasion, he presents all 
the aspect of the most perfect health. When, however, the dis- 
ease becomes of long duration, the subject of it will be apt to 
fall off his appetite, to grow thin, and to lose his condition for 
work from the gradual wasting of his powers. Indeed, there 
occur cases in which this privation of rest (from continual ex- 
citement) brings on complete marasm, and such inability for 
work, that the proprietor feels himself compelled to get rid of 
his horse at any price. 
What is the nature of this singular affection, whose most 
striking characters are, the suddenness of its appearance and 
the rapidity with which it spreads over the entire surface of 
the skin, leaving everywhere uniform marks, vestiges of its 
presence, viz. depilation in circular patches of the skin, and a 
terrible sense of itchiness, without intermission and with even- 
ing exacerbation I 
But that we may be furnished with the elements of complete 
solution of this question, let us first establish by well-authenti- 
cated facts the circumstances under which the disease ordinarily 
makes its appearance. 
