mations de bosselures a grands
rayons, passage d'une forme arrondie a une forme ovulaire ou bilobee
etc. Ces mouvements etaient visibles dans les observations I et IV et
appartenaient surtout a des globules de grande taille." It is naturally
impossible to decide if these minute movements suffice for a spontaneous
locomotion. But one cannot exclude off-hand the supposition that they
do. It is indeed supported by a further observation of Jolly on the
mononuclear eosinophil cells of the marrow. Hitherto it was taken for
established that these cells are completely devoid of spontaneous
movement. Jolly however was recently able to examine a specimen from a
case of typical leukaemia, =in which nearly all the eosinophil cells
shewed active movement=. He says: "Ces globules granuleux actifs
presentaient des mouvements de progression et des changements de forme
caracteristiques et rapides; cependant je n'ai pas vu ces globules
presenter de pseudopodes effiles; de plus, leurs contours restaient
presque toujours assez nettement arretes. Ces particularites
correspondent exactement a la description, qu'a donnee depuis longtemps
Max Schultze des mouvements des cellules granuleuses du sang normal."
Examination of dry specimens from the same case shewed, as Jolly
expressly mentioned, that the blood contained, as leukaemic blood always
does, polynuclear and mononuclear eosinophil cells. In contrast then
with all earlier observations, Jolly has demonstrated an active
spontaneous movement of the mononuclear eosinophil cells. The amoeboid
movement of the mononuclear cells is so seldom seen, not because they
lack this function, but obviously from defects in the methods of
investigation, which as is manifest are rather rough and wholly unsuited
for delicate biological processes. There are many instances in the
literature of the failures of this method, even in the case of cells
with undisputed mobility. Thus Rieder failed to observe any
contractility in the majority of polynuclear leucocytes in a case of
malignant lymphoma, whereas according to all other observations they
possess this property without exception.

We think then we must draw the conclusion that the feeble mobility of
the mononuclear cells, both eosinophilous and polynuclear, is only
apparent, and is owing to the gross method of investigation. In reality
they doubtless have mobility sufficient for emigration.

A further, but much less weighty objection to the view that myeloge