454 H. E. JORDAN 
On the other hand, the common property of pseudopod for- 
mation and constriction possessed by all the types of leucocytes 
within the marrow casts doubt upon the specific nature of the 
process as restricted to megakaryocytes of mammalian marrow. 
In the frog marrow, primitive lymphocytes, eosinophilic leu- 
cocytes and hemoblasts produce ‘hyaline’ bodies by this 
method of pseudopod ‘segmentation.’ The neutrophils produce 
granulated bodies, resembling platelets. Basophilic leucocytes, 
and to some extent eosinophiles, likewise produce granulated 
globules. The evidence seems to indicate that this property is 
common to both lymphocytes and granulocytes, and that plate- 
let-like bodies are formed only incidentally. A thorough study 
of the giant-cells of rabbit and guinea-pig also leads to the con- 
clusion that these cells produce platelets to some extent by a 
constriction of pseudopods, but chiefly by a process of fragmen- 
tation of large cytoplasmic areas of degenerating giant cells. 
The degeneration is indicated chiefly by the irregular and pyc- 
notice character of the nucleus. Similarly, in the case of throm- 
bocytes and leucocytes with metachromatic granules, degenera- 
tion involves a fragmentation of the cytoplasm and the incidental 
formation of platelet-like bodies. 
In this connection must be considered the question whether 
the cells above described as polymorphonuclear neutrophils are 
actually such or only types of non-granular leucocytes, as main- 
tained by Werzberg.2> Werzberg’s failure to interpret these 
cells as granulocytes must be ascribed to his disregard of the 
Wright or a similarly favorable technic. Studied with the 
Wright technic, the metachromatic granular content is con- 
spicuous and indubitable. This conclusion agrees with the 
earlier one of Niegolewski!® and the later one of Downey.*° 
Downey® made a special study of the polymorphonucleated 
leucocytes of the amphibian Amblystoma. He employed only 
smear preparations; these were stained with Wright’s blood 
stain. He describes their granules as ‘azurophil,’ which he 
regards as close to the ‘special’ granules of the higher animals, 
i.e., the neutrophilic granules of the polymorphs of certain mam- 
mals. He agrees with Werzberg®* that the lymphocytes of most 
