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numerary spleens is of special or at least of crucial significance. 
The framework as a whole differs only in the absence of trabeculae 
in the smaller nodes, and no important differences were noticed in the 
nature of the capsule except that it is often indefinite or trabeculated 
or absent altogether in places. The cellular content is practically the 
same except that the supernumerary spleens contain proportionately 
more blood and that there is generally not such a uniform mixture 
of erythrocytes and leucocytes. They also contain less pigment and 
far more megakaryocytes although such generalizations are of doubtful 
value. Comparatively large veins are also frequently found in section 
and can not infrequently be seen opening directly into the parenchyma 
but the arteries are comparatively inconspicuous and entirely absent 
in the smallest specimens seen a section of which did not quite fill 
the oil immersion field of the microscope. 
The character of the capsule of supernumerary spleens seems to 
be determined somewhat or at least dependent to some extent upon 
their location. Those that lie between the two layers of the peritoneum 
and are not surrounded by fat or a meshwork of connective tissue, 
usually have a very tbin but definite capsule while those which lie 
in fat frequently show no delimitation from the latter in certain areas. 
In other instances the whole capsule is formed by a loose meshwork 
of connective tissue containing parenchyma, which is condensed some- 
what toward the periphery but becomes opener toward the interior 
and gradually goes over into the reticulum of the node. In still other 
cases the splenic nodule is apparently extending beyond the capsule 
which is bordered on both sides by similar parenchyma, the outer or 
extra-capsular zone being in direct contact with the surrounding fibrous 
or adipous tissue. 
A marked difference in the surface aspect of large hemal nodes 
and the largest — about 8 mm in diameter — supernumerary spleens 
was always noted however. The latter have the color and the some- 
what roughened surface characteristic of the main spleen while large 
hemal nodes almost invariably have a smooth surface. Moreover, few 
chocolate-colored supernumerary spleens were seen in dogs and cats 
while hemal nodes of this color are not at all uncommon in the sheep 
but in contrasting the smallest supernumerary spleens found in dogs 
and cats with the smallest hemal nodes of sheep, goats and bovines 
their close resemblance or identity even is very striking. Indeed this 
resemblance is so marked that were it not for the specific differences 
