68 GENERAL CHEMICAL AND PHYSICAL CHARACTERS 



in which G represents the globin radical (page 26). According to Zinoffsky 

 (Zeit. f. physiolog. Chemie, 1886, x, 16), the molecule may be regarded as 

 consisting of two molecules of globin and one molecule of hematin. Whether 

 or not globin and hematin are thus combined, or the hematin is linked with 

 one or several molecules of globin; whether the globin is a simple or com- 

 pound body; whether the hematin may be combined with polymeric or 

 isomeric forms of globin; whether the hematin is with certainty a uniform 

 substance, etc., are still open questions. If, as Miescher states, the albumin 

 molecule with its 40 atoms of carbon may have as many as a billion stereo- 

 isomers, what may be the possibilities of hemoglobin or globin molecules 

 with their hundreds of carbon atoms? Whatever may be the chemical 

 relations between globin and hematin, they are so peculiarly associated that 

 undecomposed hemoglobin gives neither albuminous nor iron color reactions. 

 It is of incidental interest to note that, except the iron in hemoglobin, 

 nearly all of the iron of the tissue cells is contained in the nucleoproteins, 

 and that while these substances, unlike hemoglobin, yield the protein 

 color reactions, they, like hemoglobin, do not yield iron reactions, show- 

 ing that in both the iron is in a non-ionic or "masked" state. 



We are also in doubt as to the state or states in which hemoglobin 

 exists in the erythrocytes, especially as to whether it is in a liquid, semi- 

 liquid, or solid form, and as to the nature of the compound or compounds 

 it probably forms with other constituents of the erythrocytes. The red 

 corpuscles consist of a stroma and hemoglobin with other substances. 

 The former is elastic, non-contractile, seemingly homogeneous, colorless, 

 transparent, and albuminous. According to some, the stroma is in the form 

 of minute sacs which contain hemoglobin and other substances in solution. 

 According to others, it is in the form of a protoplasmic mass, throughout 

 which the hemoglobin and other substances are distributed. That the 

 hemoglobin is not in either crystalline or amorphous form has been shown 

 by microscopic examination with high powers; and that it is not in solu- 

 tion in a free state seems obvious from the fact that in the case at least 

 of the very insoluble forms of hemoglobin, as in the guinea-pig, squirrel, 

 rat, necturus, etc., not only are the water and the inorganic salts of the 

 corpuscles wholly inadequate to dissolve or keep in solution the hemo- 

 globin, but even the entire blood plasma is altogether insufficient to hold 

 the hemoglobin in solution when freed from the corpuscles. 



The assumption of Preyer that the hemoglobin is held in solution in 

 the corpuscles by virtue of potassium salts because of the presence of a 

 relatively high percentage of those salts in comparison with the percentage 

 in the plasma, and because of the higher solubility of the hemoglobin in 

 water when these salts are present, is not worthy of consideration, inas- 

 much as in certain bloods, for instance in those of the dog and cat, the per- 

 centage of potassium in the corpuscles is practically the same as in the 

 plasma, and yet in the dog crystallization takes place rapidly in the plasma 

 upon the laking of the blood. Rywosch (Centralbl. f . Physiologic, 1905, xix, 

 388) believes that the hemoglobin is present in the corpuscles in a free 

 state. He found, after destruction of the erythrocytes by grinding in sand, 



