Chaii^i^cs in the Erythrocytes in Anccniias. 159 



phenomena of suffocation, lowering of blood pressure and uncon- 

 sciousness (ansemia of the brain). After haiimorrhage proteid 

 /netabolism is increased; metabohsm of fats is. however, decreased 

 because of the diminished power of combustion. Hence repeated 

 venesections are appropriate treatment where it is desired to in- 

 crease the deposition of fat and tlic\- are employed as aids to fat- 

 tening animals. 



General anaemia may also be brought about by insufficient nutri- 

 tion or improper assimilation of food, as well as by diseases and 

 injuries of those tissues which supply definite blood constituents. 

 Here are particularly included various affections of the stomach and 

 intestine, hepatic diseases and alterations of the lymphatic tissues ; 

 but in arldition to such disturbances there is a wide further possi- 

 bility of the establishment of an ansemia from disease of the many 

 other tissues which contribute to blood formation. A number of 

 agencies are known to be capable of inducing the condition by caus- 

 ing the destruction of the blood corpuscles, perhaps to such a de- 

 gree that regenerative effort can no longer efficiently restore the 

 loss, as certain parasites of the blood (trypanosomes) and poison- 

 ous or toxic products of metabolism. 



Among the most notable symptoms of man\- anremias are 

 changes in the form and structure of the erythrocytes. In place 

 of the circular discs there may be met irregular pyriform, club- 

 shaped or indented elements of various size, cells containing 

 vacuoles (cavities, hollow spaces), and nucleated red corpuscles. 

 A blood preparation showing such multiform cells of varying ap- 

 pearances is said to exhibit poikilocytosis ( ttoikIXos, variable, con- 

 fused, involved). Recently alterations in the staining reactions 

 of the corpuscles have been made out. The normal cells invariably 

 take up only one tint from certain staining combinations; the 

 stroma of young forms, degenerating and dead cells, however, 

 may assume several colors (polychromatophUia). The occurence 

 of nucleated red corpuscles in the circulating blood is an evidence 

 of active regeneration of these elements, and is often encountered 

 in the anaemias. Especially large cells of this type are sometimes 

 met {megalohlasts, gigantobhtsts), a peculiarity interpreted as 

 evidence that regeneration is taking place with extreme haste, 

 such cells, otherwise only seen in the bone marrow as early stages 

 of the erythrocytes, entering the circulation in these cases as im- 

 mature elements (Krehl). The increased cellular muhiplication 

 in the bone marrow, the principal site of the formation of erythro- 



