In practical medicine the term "anæmia" has not quite the restricted sense that scientific investigation gives it. The former regards certain striking symptoms as characteristic of the anæmic 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 anæmia 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 anæmic 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 "anæmia" 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 anæmias we can at once exclude from our consideration.