298 H. E. JORDAN 
THE SIGNIFICANCE OF THE SO-CALLED MITOTIC FIGURES 
Review of literature 
Under this head also the investigation of Denys is in this con- 
nection by far the most important. Denys (4) alone gives a 
detailed account, with adequate illustrations, of what he believed 
to be mitotic division of the hemogenic giant-cells of red bone- 
marrow. Arnold’s (1, 2) account obviously relates to degener- 
ative changes, as already suggested by Dickson. Dickson (5) 
desires his own account of mitosis in these cells to be accepted’ 
only as a ‘preliminary sketch.’ Bunting (3) merely refers to the 
mitotic division of these cells, without giving any detailed de- 
scription or illustrations. Heidenhain gives us only meager de- 
tails of what he regards as multipolar (‘multiple’) mitoses of these 
giant cells (pp. 622-625 (8)). The statement by Van Bambeke 
and Van der Stricht (16) that the lobulated nucleus of the mega- 
karyocyte is formed by fusion of a large number of small daugh- 
ter-nuclei during the telophase of many repeated multipolar 
mitoses, is hardly more than a suggestion. Nevertheless, these 
less complete accounts of an alleged mitotic process will be briefly 
considered after a detailed analysis of Denys’ evidence for mitosis. 
Mitosis is said by Denys to be initiated by the rearrangement 
of the chromatin into a densely wound thread, like the close spi- 
reme of binary mitotic division (figs. 23, 24, 18, and 12). Subse- 
quently this spireme segments into short rods (chromosomes?) 
which arrange themselves first into a spherical mass (fig. 14), 
and later into what is described as a ‘basket structure with polyg- 
onal meshes.’ Figure 15 illustrates well the several varieties of 
this latter stage as figured by Denys. ‘This stage is said to rep- 
resent that of the equatorial plate of binary mitosis, just preced- 
ing the longitudinal division of the chromosomes. Denys de- 
seribes the shape of the alleged chromosomes at this stage as 
having the form of a U with the bend of the U directed toward 
the center of the nucleus. Presently they are believed to suffer 
a longitudinal splitting, after which the daughter groups of 
chromosomes separate and take positions as the polar groups of 
multipolar mitoses (fig. 5). These groups are then said to re- 
