CRYSTALLOGRAPHY OF THE HEMOGLOBINS OF AVES. 



171 



Reduced Hemoglobin of Corvus americanus. 



Monoclinic: Ratio of a : 6 =1 : 1.044; 0=50 30'. 



Forms observed: Orthopinacoid (100), clinopinacoid (010), base (001), positive 

 hemiorthodome (101). No prism was definitely observed. 



Angles: 100 A 001=0 = 50 30' (129 30'); 100 A 010 = 90; 001 A 010=90; 

 100 A 001=63. 



Habit more distinctly orthorhombic than the oxyhemoglobin crystals; tabular 

 by development on (010) and nearly equidimensional in many cases, not elongated verti- 

 cally, but in nearly regular rhombic plates (text figure 57). It forms regular growths 

 with the oxyhemoglobin (see plate 15, fig. 88). 



Color the usual reduced hemoglobin purplish-red. 



The optical characters were not determined for this form of crystal and perhaps 

 it may be orthorhombic. The cleavage in the direction of the vertical axis is not notice- 

 ably stronger than parallel to a, hence it might be a prismatic cleavage in the orthorhombic 

 system. 



TABLE 36. Some of the characters of the crystals of the oxyhemoglobins of the Aves. 



