PATHOLOGY OF EQUINE SYPHILIS. 
495 
cessivs sections; and in the posterior gray cornua are seen cavi¬ 
ties, 1. cm. broad, extending through many sections and destroy¬ 
ing the cornua. Dr. Thanhoffer thinks the former due to a 
tubular, or syringo-myelitis , following extravasation around the 
central canal,—the inflamed tissue degenerating and being ab¬ 
sorbed, leaves the vacuoles. 
New formations of connective tissue occur in both white and 
gray substance, and in other cases, the posterior cornua are re¬ 
placed by shrivelled connective-tissue bands. 
The spinal meninges sometimes show congestion and the 
same changes of blood-vessels noted elsewhere in the cord. 
In a few cases, the nerve-roots showed atrophy; fatty, or con¬ 
nective-tissue degeneration, and loss of axis cylinder. 
The cells of nerve ganglia undergo essentially the same 
changes as the cells in the spinal cord. The ischiatic nerves show 
no marked changes. 
The “ thalerflecJce” or sharply-defined skin swellings, so char¬ 
acteristic of equine syphilis in all its stages, are due mainly to 
disease of the corium, and consist of a saturation—principally 
about the sweat glands and arrectores piiorum —with small gran¬ 
ules, apparently due partly to cell-migration and partly to cell- 
proliferation. The cause of these thalerjlecke Dr. Thanhoffer be¬ 
lieves to be the aforementioned changes in the cord, its roots and 
ganglia. Decent anatomical investigations have shown that the 
nerves of the skin and muscles of the rump take their origin 
from the lumbar region, that place from which also the genitals 
and posterior extremities receive their innervation ; indeed, ac¬ 
cording to the more recent investigations of Strieker, Luchsinger 
and others, from here spring also the vasomoter nerves of the 
extremities. It is further noteworthy that the thalerfleeke occur 
mainly on the rump and thigh (and further of flank W.), and are 
rarely seen on the head and neck; but this may happen without 
contradicting the foregoing, since in severe cases the cervical 
cord and, in the last stages, even the medulla or the brain itself 
may become affected. But thalerflecJce are by far more common 
on those parts receiving their innervation from the lower dorsal, 
or lumbo-sacral cord, where in all stages of the disease by far the 
most serious changes are noted. 
