RED BLOOD-CORPUSCLES. 275 



be closely related to the hyaline substance (hyaline substance of ROVIDA), 

 occurring in the lymph-cells. In the mass extracted by alcohol from 

 the blood-corpuscles of the hen, ACKERMANN found 3.93 per cent phos- 

 phorus and 17.2 per cent nitrogen, which on calculation gave 42.10 per 

 cent nucleic acid and 57.82 per cent histone. PIETTRE and VILA l found, 

 in the -stromata, 0.3 per cent phosphorus in the horse and 2.3-2.6 per 

 cent in birds (ducks and hens) , calculated on the ash-free substance. They 

 found the quantity of nitrogen to be 11.7 and 13.21 per cent for the horse 

 and dog respectively. The non-nucleated red blood-corpuscles are, 

 as a rule, very poor in protein, but rich in haemoglobin; the nucleated 

 corpuscles are richer in protein and poorer in haemoglobin than the 

 non-nucleated. The reducing substances, and in certain animal sugars, 

 probably also conjugated glucuronic acids and several enzymes, among 

 which occurs the proteolytic enzyme studied by ABDERHALD'EN and col- 

 laborators, 2 belong to the stromata. It is difficult to decide in many 

 cases whether the enzymes found in the blood belong to the fluid or to 

 the various kinds of form-elements. 



A gelatinous, fibrin-like protein body may be obtained from the red 

 blood-corpuscles under certain circumstances. This fibrin-like mass 

 has been observed on freezing and then thawing the sediment of the 

 blood-corpuscles, or on discharging the spark from a large Leyden jar 

 through the blood, or on dissolving the blood-corpuscles of one kind of 

 animal in the serum of another (LANDOIS, stroma-fibriri) ; i.e., in the so- 

 called hcemagglutination, a clumping of the red blood-corpuscles into 

 clusters takes place. This agglutination can be brought about by bodies 

 similar to the hsemolysines and also by serum constituents produced 

 normally or by immunization. It has not been shown that a fibrin for- 

 mation from the stroma takes place, nor is it probable. Fibrinogen 

 has been detected only in the red corpuscles of frog's blood (ALEX. SCHMIDT 

 and SEMMER S ). 



Closely related to the anatomical and chemical structure of the eiythro- 

 cytes is the question, which is important for the metabolism in the blood, 

 as to the permeability of the erythrocytes, that is, their power of tak- 

 ing up substances of different kinds. This question as well as the per- 

 meability of the blood-corpuscles for anions under the influence of carbon 

 dioxide has been discussed in Chapter I, pages 7 and 8. 



The mineral bodies of the red corpuscles will be treated in connection 

 with their quantitative constitution. 



1 Ackermann, Zeitschr. f. physiol. Chem., 43; Piettre and Vila, Compt. Rend., 143. 



2 Zeitschr. f. physiol. Chem., 51, 53 and 55. 



3 Landois, Centralbl. f. d. med. Wissensch., 1874, 421; Schmidt, Pfliiger's Arch., 

 11, 550-559. 



