44() H. E. JORDAN 
that of the smallest, with a larger nucleus and a more expansive 
shell of cytoplasm. All the various sizes of lymphocytes have a 
common type of nucleus, which stains deeply as a whole, due to 
a coarse close-meshed reticulum with many net-knots. It 
assumes a deep lilac color. Grouped according to. size, the 
lymphocytes may be classified as large and small, but abun- 
dant transition forms occur (figs. 6 to 10). Their resemblance to 
mammalian lymphocytes is striking. 
The most characteristic features of these lymphocytes are 
their apparently granular cytoplasmic content and their numer- 
ous pseudopods (figs. 5 and 7). Various distortions, nuclear 
as well as cytoplasmic, demonstrate that these cells are extra- 
ordinarily delicate. The cytoplasm is extremely viscid. Some 
of the ‘pseudopods’ are most probably artifacts. But that 
at least many should not be so interpreted is sufficiently indi- 
cated by the fact that these same cells, or their ancestors, in the 
sections of bone-marrow likewise are covered with abundant 
pseudopods. For the same reason certain isolated portions of 
such pseudopods (fig. 7) must be regarded as actual constrictions 
or segmentation products. 
In the bone-marrow the lymphocytes have a homogeneous 
basophilic cytoplasm (figs. 34 to 40); in the blood smears they 
appear to have a coarsely granular basophilic cytoplasm; the 
‘oranules’ are very irregular in form and size and frequently 
appear massed into clumps (fig. 9). It seems possible that the 
granules in question are in fact fixation artifacts, that is, proteid 
coagula of the basophilic cytoplasm. However, certain of the 
lymphocytes in the blood contain also metachromatic granules 
scattered throughout the basophilic substratum. These would 
seem to correspond with the ‘leucocytoid lymphocytes’ of Werz- 
berg, which this author regards as a distinct class. The evi- 
dence seems to indicate that the potentiality to form metachro- 
matic granules is a common property of the lymphocytes. There 
is no good reason, in my opinion, for classifying lymphocytes on 
the basis of the presence of ‘azurophil’ granules. ‘Lymphocytes’ 
comprise a group of cells characterized by common nuclear and 
fundamental cytoplasmic (basophilic) ¢haracteristics; they vary 
