CRYSTALLOGRAPHY OF THE HEMOGLOBINS OF AVES. 



169 



Pleochroism is very strong; a colorless or nearly so, b deep brownish-red, c very 

 deep brownish-purple. The absorption for c and b is very strong. Double refraction 

 strong; the extinction is straight on edge views and symmetrical on the base. Orienta- 

 tion of the elasticity axes is a = 6, 6 = a, c=6. On the base, traces of an interference 

 figure are seen, but the brushes pass out 

 of the field; looking along a the complete 

 figure is seen, showing that the acute 

 bisectrix Bx a = a, and the optical char- 

 acter is negative. This was confirmed by 

 observations with the quartz wedge upon 

 the interference figure. 



52 



Flos. 61. 62. Colamba lima Metoxyhemoglobin. 

 Flo. 53. Columba livia 3-Oxyhemoglobin. 



5.1 



Reduced Hemoglobin of Columba livia. 



Orthorhombic (?). 



In fine needle-like crystals, grow- 

 ing in tufts, often on the 6-type of crys- 

 tals in a sort of regular growth, also not 

 connected with other types of crystals. 



The double refraction is rather strong; the extinction is straight. The length of the needles 

 appears to be the direction of greatest elasticity ; the pleochroic color of a is rose-pink. 

 The directions of less elasticity normal to this show deep purplish-red colors. The crystals 

 were not well enough formed to make out much as to their characters. 



Schwantka (Zeit. fur physiolog. Chem., 1900, xxx, 486) examined 

 crystals of oxyhemoglobin of pigeon's blood that were prepared by A. 

 Kossel, which were sufficiently large to be measured on the reflecting 

 goniometer. The examination was conducted at a room temperature of 

 between 5 and 10 C. Schwantka's description furnishes the following data : 



^-Oxy hemoglobin of Columba livia. 



Tetragonal sphenoidal: Axial ratio a : 6 = 1 : 1.175. 



Forms observed: Unit prism (110), unit sphenoid (111). 



Angles: Prism angle 110 A 110=90; prism to sphenoid 110 A 111=31; sphe- 

 noid faces over pole 111 A III = 118 6'; sphenoid faces 111 A lTT = 106 39' (calculated 

 108 18'). 



The crystals consisted of the unit prism and the sphenoid, with somewhat prismatic 

 development, elongated on the vertical axis and sometimes flattened on two opposite 

 prism faces, making the crystal somewhat tabular (text figure 53) . In many crystals a 

 face produced by contact with the vessel in which the crystals were grown was seen; 

 this was vicinal to the prism face (110), but it did not give good reflections. The develop- 

 ment of this accidental face caused a distorted appearance. What seems to be parallel 

 growth was also observed. 



The crystals were determined to be uniaxial and showed only a weak pleochroism, 

 changing from a brighter to a duller red. They extinguished parallel to the vertical 

 axis. The optical character is not recorded. 



CROW, Corvus americanus. Plates 14 and 15. 



The fresh blood was obtained from the living bird and was allowed to 

 clot. This clot was ground up with sand and with a large excess of ether 

 and centrifugalized ; afterwards the clear fluid was oxalated. The prep- 

 arations were made as usual and the crystals began to form soon after the 

 slides were covered. The slides stood for several days before they were 



