no DISEASE IN WILD MAMMALS AND BIRDS 
groups are concerned, one can state with reasonable 
certainty that they differ little throughout the animal 
kingdom. They occur in islands, strands, or infiltrate — 
like groups, are mixed granular and non-granular in 
character and, with exception of the frankly oxy- 
philic cells, are distinctly basic in tinctorial affinity. 
In a case probably myeloma, soon to be discussed, 
there is not a single acidophilic or multinucleated 
cell to be found in two sections. As might be expected 
from the greater eosinophilic content of the circulating 
blood in the Aves, greater numbers of such cells are to be 
found in the marrow and they are, understandingly 
enough, sometimes found in distinct nodes and groups 
containing mono- and polynuclear varieties. Concerning 
the platelets, no sufficient data are at our disposal to war- 
rant a general statement. In the avian marrow they can 
be made out quite clearly, as in the blood, and have a 
greater diameter and a sharper, more chromatic nucleus 
than in the higher mammalian blood. Mast cells are quite 
common in lower mammals and birds, in whose blood they 
maintain an appreciable percentage, while in the marrow 
they stand out clearly. It is noteworthy, in the light of 
Graham's statement that the hemic basophile is but a 
degeneration form of the eosinophile, that in the bird's 
marrow, large mono- and polynuclear cells with both 
kinds of granules easily may be found by Romanowsky 
stain. An increase of eosinophiles, seen in avian as well 
as in human parasitism, is not necessarily accompanied 
by basophilia. 
Hyperplasia and atrophy of marrow in the lower 
mammals follow much the same conditions as in higher 
groups. During acute general infections, as by the para- 
colon bacillus in carnivores, it is common to find a distinct 
increase in the mononuclear centres, while in suppu- 
rative lesions a pohTiucleosis results. The bird, 
however, responds less readily with leucocytes, judged 
bv cross sections of blood vessels and the activity of the 
