334 
PROFESSOR POUCHET. 
hsematid, to this end undergoing a sort of abortion or 
degeneration. 
The protoplasm now commences to form hsemoglobin ; the 
presence of the latter seems to be shown from the first by 
the shape which the protoplasm assumes, which is already a 
geometrical one. 
The nucleus does not multiply; the element which has 
thus undergone haemoglobic degeneration has reached by the 
process its ultimate form, and is destined to disappear more 
or less slowly. The nucleus, as it takes on an oval shape, 
in accordance with the elongated shape of the protoplasm, 
seems to lose that power of dividing and multiplying which 
it originally possessed. The protoplasm increases and com- 
mences to take on a yellow colour, visible with a microscope, 
on account of a continued accumulation of haemoglobin. 
Soon it has entirely lost its essential vital properties, 
sensation, and power of movement. It becomes, with its 
nucleus, a passive body like the cells of the horny layer of 
the epidermis, retaining its chemical affinities, but devoting 
itself entirely to this chemical function of haemoglobic de- 
generation. Haemoglobin continues to accumulate in the 
protoplasm, which thus becomes more and more dense and 
coloured. 
The nucleus loses its chemical characters and the proto- 
plasm soon constitutes a homogeneous mass, which is finally 
dissolved in the blood plasma ; it may be while still in the 
circulation ; it may be, on the other hand, after having been 
stopped on account of its diminished elasticity in the paren- 
chymatous tissue of the spleen. 
I believe I was the first to completely describe the suc- 
cessive stages of this development, as well as a certain 
number of points of less importance which go along with it, 
but on which it is useless to dwell in this rapid resume, 
M. Hayem has called the young corpuscles, the bodies of 
which are already flattened, oval, and still appear colourless, 
it may be, on account of the extent to which they are 
magnified, haematoblasts. 
It seems certain that these young corpuscles are at least 
capable of changing their shape in the blood in a state of 
rest, as do the nuclei of origin and the adult leucocytes. 
M. Hayem admits the transformation of his haematoblasts 
into corpuscles. 
But M. Vulpian (‘ Comptes Rendus,’ 4th June, 1877) 
certainly lias the credit of having demonstrated this develop- 
ment ; he has shown by careful experiments tliatin the blood 
of dead frogs luematoblasts always appear in large numbers. 
