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CRYSTALLOGRAPHY OF THE HEMOGLOBINS 



FIGS. 1, 2. Raid l&vis Oxyhemoglobin. 

 1 ic. M. Acipenaer sturio Oxyhemoglobin. 



produce sheaf-shaped and fan-shaped groups, and 

 on the flat show the irregularly overlapping plates 

 (see plate 1, figs. 1, 2, 3). Frequently the orienta- 

 tion of the crystals in a group is such that the 

 entire group extinguishes simultaneously in polar- 

 ized light. 



Extinction is symmetrical when the plate is 

 viewed on the base (001), and parallel when viewed 

 on edge (orthorhombic) . The interference figure 

 was not observed, but, from the pleochroism and 

 the elasticities of the axes as observed, the orienta- 

 tion of the elasticity axes with reference to the 

 crystal axes is as follows (text figure 2) : a = b, b a, 

 ( = 6. From the fact that the figure could not be 

 seen when looking along a and t, and from the 

 elasticities and pleochroism, the acute bisectrix of 

 the optic axes Bx a = a. The optical character is 

 hence negative. 



Three species of the Teleostomi or Bony Fishes were examined. In the 

 order Actinopterygii the common sturgeon, Acipenser sturio, was examined. 



STURGEON, Acipenser sturio. Plates 1 and 2. 



The blood was obtained from the living fish, oxalated, ether-laked, 

 and centrifugalized, giving a clear solution, from which the preparations 

 were made in the usual manner. The slides were prepared inside of 4 hours 

 from the time of the bleeding of the fish. The crystals are deposited rapidly 

 from the solution, and inside of a few minutes after the blood is placed 

 upon the slide an abundant crop of small lath-shaped crystals has formed. 

 After 1 hour the entire slide is filled with a felt of these crystals, and the 

 solution is colorless. No particular change in the slides was noted after 

 this condition was reached, showing that the crystals were quite insoluble 

 in the plasma. 



In order to retard the rate of formation of the crystals a portion of the 

 oxalated normal blood, which was found to be filled with crystals after 

 standing 24 hours, was diluted with 5 volumes of water and centrifugalized. 

 The clear supernatant liquid was then used to make slide preparations, 

 but while it readily crystallized, the crystals were not so perfect as those 

 made from the whole blood. The crystals from the whole blood were 

 therefore used for the examination. 



The color of the crystals, a brownish-red, indicated that they were 

 Oxyhemoglobin mixed with some methemoglobin, which latter was observed 

 in the normal blood of other fish when obtained fresh from the living animal. 

 The blood was not examined by the spectroscope. 



The crystallographic description of the crystals is as follows: 



Oxyhemoglobin of Acipenser sturio. 



Orthorhombic: Axial ratio not determined, only one fundamental angle being 

 observed, and that a doubtful one. 



Forms observed: Macropinacoid (100), brachypinacoid (010), brachydome (Oil). 



