536 
S. STEWART. 
Actinomycosis is the most prevalent disease of cattle in this 
section of the country, and in at least 8o per cent, of the cases 
in cattle offered for sale at the market the lesions of the malady 
are confined to the structures of the head and neck. Indeed, in 
most cases it is a local affection, in no way affecting the general 
system, excepting as it interferes with prehension, mastication 
and deglutition of food. The majority of cases involve the in¬ 
ferior or superior maxillary bones. In all these cases coming 
under my notice there were found to be from one to six or more 
fistulous tracts, discharging into the cavity of the mouth. 
These fistulse are to be found before the disease has reached suf¬ 
ficient development to be observable by visual examination ex¬ 
ternally, and long before the overlying skin has been involved 
in any degree. A careful examination of the internal organs of 
many cattle having actinomycosis of the maxilla in the early 
stage but with fistulae in the mouth has failed to reveal the in¬ 
volvement of any visceral organ. As stated before, the lesions 
of the disease are to be found usually in the tissues about the 
head and neck. When the soft structure only are involved it 
usually begins in one or more of a chain of lymphatic nodes, 
extending from the mouth to the thorax, most frequently in the 
sub-maxillary region. The disease processes set up in these 
nodes, destroy them and in their stead is developed a dense, 
thick-walled sac of variable size, containing a whitish, odorless 
fluid or semi-fluid mass, which, it is claimed, “ consists of detri- 
tis resembling pus but lacking the specific micrococci which are 
always present in pus.” The skin over these tumors may be 
involved and a fistula established, the external end of which is 
surrounded by a granular growth, which necroses on the sur¬ 
face, giving off a very offensive odor and has a disgusting ap¬ 
pearance. Extension to other parts is more frequent when the 
disease is glandular in character. 
In about 20 per cent, of cases the fungus invades the soft 
parts about the head and neck, many of these present actinomy¬ 
cotic growths in the lungs and occasionally the liver and intes¬ 
tinal structures are invaded. The disease appears to extend 
