306 Sir Evei^rd Home on the 
are of a small size, but from that representation no conclu¬ 
sions can be drawn, either as to their origin, or their real 
situation respecting the healthy structure of the organ. 
In the second, which he mentions to be more rarely met 
with, they are shown both on the convex and concave sur¬ 
faces close to one another, immediately under the surface, 
and projecting through the pleura; these have acquired a 
considerable size, and it is much to be regretted that they 
were not met with in an earlier stage, and that the history of 
this particular case has not been registered; but when the 
appearance, which is shown, and the section of the tubercle 
is accurately observed, no one can doubt that the origin of 
this species of tubercle must have been from particles of 
coagulable lymph deposited in the superficial air cells, similar 
to those met with in the hare. 
EXPLANATION OF PLATE XIII. 
Fig. 1. Represents the superficial cells of the lungs of a 
hare that had been coursed, filled with colourless coagulable 
lymph ; magnified 20 diameters. 
Fig. 2. A section of the same lungs, in which the deeper 
seated cells are exposed ; magnified in the same degree. 
Fig. 3. A perpendicular section of the superficial cells ; 
in the same degree magnified. 
Fig. 4. The bronchial branches and superficial cells of a 
hare that had been coursed, filled with mercury where not 
previously occupied by coagulable lymph ; magnified 20 di¬ 
ameters. 
Fig. 5. A section of another portion of the same lung, in 
