160 
GEORGE FLEMING. 
The majority of these are soft, something like tallow; others 
may be gritty to the touch, when they are impregnated with lime 
salts. Whether occurring in animals or man, these peculiar par¬ 
ticles must always be considered diagnostic of the disease, even 
without the aid of the microscope. 
When the nodules are removed from the connective-tissue 
stroma, this is found to be cavernous in its structure, from the 
large number of small cavities they occupied—another charac¬ 
teristic feature of the tumor. 
I have already alluded to the histological characters of the 
nodules. 
As to the manner in which, and channel by which, the fungus 
invades the tissues, there is no satisfactory evidence. It is, how¬ 
ever, extremely probable that it enters, in the form of spores, 
through a wound, abrasion, fissure, or even by means of the 
delicate mucous follicles of the membrane lining the lips, mouth, 
pharynx and nostrils—in fact, any part of the digestive or respi¬ 
ratory canal. It has been shown that it may exist harmlessly in 
large numbers in the tonsilar glands of the pig, probably waiting 
for a casual abrasion or removal of the epithelium, in order that 
it may rapidly develop in the tissues beneath. 
This injury may be inflicted in many ways, and very likely 
by the food upon which the animals most liable to the disease 
are fed. I am informed by a practitioner in Lincolnshire, that 
the malady is most frequent after cattle have been fed on straw, 
barley and chaff; and this may not only injure the mouth, but 
serve also as the vehicle for transmission of the fungus—straw 
being so often mouldy, and infested with vegetable parasites of 
various kinds. 
The species of animal invaded by the actinomyces appears to 
have much influence on the pathological results. In man the 
tendency is to suppurative processes and metastatic abscesses; 
while in animals it is to new-formation tumors, and induration or 
degeneration of tissues—be they hard or soft; the extension of 
the fungus being progressive by means of its spores, which arc 
disseminated, localize themselves^ fructify and produce the cha¬ 
racteristic changes in their surroundings. These spores may 
