THE BLOOD 327 



the normal forms of leukocytes, and by preference with an increase in the 

 number of polynuclear neutrophilic forms and of the lymphocytes, while ab- 

 normal forms, as, for instance, the myelocytes (large leukocytes, with one 

 nucleus and with neutrophilic granules) belong to the exceptions. 



To sum up, we may say that the leukocytes do not plaij a role of any 

 importance in the blood changes of chlorosis. 



The third formed constituents of the blood, the so-called " blood plaques," 

 attract especial attention in chlorosis because here they appear in remarkably 

 increased numbers, sO that large groups of these small colorless structures 

 may often be seen in each field of the fresh preparation. 



We are still uncertain as to their significance. Some authors, for instance, 

 the pupils of Arnold, consider them as a segmentation product of the red 

 blood cells, while others believe them to be fragments of disintegrated nuclear 

 substance. 



Since these small bodies, as I have repeatedly noted in many examinations, 

 may be partially stained with basic stains, especially well with methylene- 

 blue, and partially with certain nuclear stains, for instance, with Ziemann's 

 [or Leishman's] eosin methylene-blue mixture, I believe that, at least in the 

 majority of cases, they may be considered fragments of nuclear substance, and 

 at best only a small number of them may have originated from red blood cells. 



In any case, our knowledge concerning these small structures is so indefi- 

 nite that from their appearance in increased numbers in the circulating blood 

 we cannot draw any conclusion, either general or special, in regard to chlorosis. 



In uncomplicated cases of chlorosis, the blood serum shows, as a rule, no 

 noteworthy reduction in the percentage of albumin. The specific gravity of 

 the serum is on the average 1.028, which corresponds perfectly with the com- 

 position of normal serum, and the total solids appear to be normal in amount, 

 averaging about 10 per cent. [The greatest menace to the life of the chlorotic 

 is thrombosis of the cerebral sinuses. Venous thrombosis of the extremities 

 is also much commoner than in any other form of anemia. As a rule, throm- 

 bosis occurs in the severest and most chronic cases. It is very possibly con- 

 nected with the excess of platelets in the blood. — Ed. J 



Taking into consideration all these changes, it follows that the blood in 

 chlorosis is of a peculiar composition, and characterized by the fact that the 

 normal number of blood cells is only very slightly reduced while the amount 

 of hemoglobin of the individual cell is considerably diminished, and thus a 

 peculiar relationship between the fluid constituents of the blood and the blood 

 cells develops, which is surprisingly manifest if we puncture a vein in the 

 arm, permit a few cubic centimeters of blood to flow into a tube, and centrifu- 

 gate it before it coagulates. In doing this we notice (as also when we allow 

 the bipod to coagulate spontaneously or to form a sediment) that the m.ass 

 of the red cells, in toto, is extraordinarily reduced, often to only 25 per cent, 

 of the whole blood mass, compared with 75 per cent, of the blood fluid, while 

 in normal blood both components are present in about equal proportions. 



It is obvious from the above mentioned examinations that the blood cells, 

 although present in about normal numbers, are markedly deficient in hemo- 

 globin, while the chief bulk of the blood is formed by plasma, so that this 



