CHRONIC PLEURO-PNEUMONIA. 
505 
farmers believe that it is, and I am partly of their opinion. When 
an animal falls sick in the pasture, the others, after his removal, 
go and smell at the grass where he has lain, and which he has 
covered with his saliva; and after that new cases succeed to the 
first. It is true that this fact is not conclusive, since the disease 
also appears in a great number of animals that have been widely 
separated from each other. But I have myself seen three cases 
in which the cattle of the country, perfectly well before, have 
fallen ill, and died with the same symptoms, excepting that they 
have been more acute, after they have been kept with pleuritic 
cattle. This circumstance inclines me to think that the disease 
is contagious, or, at least, that, in the progress of it, the breath 
infects the air of a cow-house in which there are other animals 
already predisposed to the same disease. I am also induced to 
believe that most of the serious internal diseases are communi¬ 
cated in this manner, and particularly those which affect the 
organs of respiration when the animals are shut up in close, low, 
and badly ventilated cowhouses. 
Rec. de Med, Vet. Mai, 1833. 
On White Tumours of the Joints. 
By M. Jacob, F.N'., 11th Dragoons. 
We designate under the name of white tumours of the joints 
those enlargements, slow in growth, hard to the touch, and 
that are situated in the soft parts which go to form the articula¬ 
tions, and in the parts that surround them. Sometimes these 
parts only are diseased; at others, the bones and articulating 
cartilages are also affected. The disease usually appears in the 
ligaments, and thence is propagated to the synovial membranes 
and the bones. 
These white tumours are produced either by exterior causes, 
or they are the consequences of rheumatic affections, or succeed 
to articular inflammation, caused by over-work ; particularly 
when that work is prematurely exacted from the animal. Their 
development is comparatively slow compared with that of phleg¬ 
mon ; and there is no symptom of acute inflammation. 
When a white tumour is dissected, there is found, successively, 
the healthy skin, a layer of cellular tissue immediately under¬ 
neath slightly infiltrated, and which infiltration gives it an ap¬ 
pearance of greater thickness. Underneath this first layer is 
found another, infiltrated by a clear yellow fluid; near the liga¬ 
ments the cellular tissue is perfectly indurated ; it creaks beneath 
the scalpel. The articular ligaments are infiltrated with a fluid of 
some consistence, and which is sometimes gelatinous. The arti- 
