gin 187

V. LEUKOPENIA 188

The blood platelets. The haemoconiae 190

INDEX TO LITERATURE 195

INDEX 209

PLATES

INTRODUCTION.

DEFINITION OF ANAEMIA. CLINICAL METHODS OF INVESTIGATION OF THE BLOOD.

In practical medicine the term "anaemia" has not quite the restricted
sense that scientific investigation gives it. The former regards certain
striking symptoms as characteristic of the anaemic condition; pallor of
the skin, a diminution of the normal redness of the mucous membranes of
the eyes, lips, mouth, and pharynx. From the presence of these phenomena
anaemia is diagnosed, and according to their greater or less intensity,
conclusions are also drawn as to the degree of the poverty of the blood.

It is evident from the first that a definition based on such a frequent
and elementary chain of symptoms will bring into line much that is
unconnected, and will perhaps omit what it should logically include.
Indeed a number of obscurities and contradictions is to be ascribed to
this circumstance.

The first task therefore of a scientific treatment of the anaemic
condition is carefully to define its extent. For this purpose the
symptoms above mentioned are little suited, however great, in their
proper place, their practical importance may be.

Etymologically the word "=anaemia=" signifies a want of the normal
=quantity of blood=. This may be "general" and affect the whole organism;
or "local" and limited to a particular region or a single organ. The
local anaemias we can at once exclude from our consideration.

_A priori_, the amount of blood may be subnormal in two senses,
quantitative and qualitative. We may have a diminution of the amount of
blood--"=Oligaemia=." Deterioration of the quality of the blood may be
quite independent of the amount of blood, and must primarily express
itself in a diminution of the physiologically important constituents.
Hence we distinguish the following chief types of alteration of the
blood; (1) diminution of the amount of Haemoglobin (=Oligochromaemia=), and
(2) diminution of the number of red blood corpuscles (=Oligocythaemia=).

We regard as anaemic all conditions of the blood where a diminution of
the amount of haemoglobin can be recognised; in by far the gr