164 



CRYSTALLOGRAPHY OF THE HEMOGLOBINS OF AVES. 



were very soluble and had to be kept at about C. during the examination 

 and photographing. Several other trials were subsequently made with the 

 same blood, but they failed to yield crystals. The crystals obtained were 

 found to be oxyhemoglobin by spectroscopic examination. 



Oxyhemoglobin of Olor buccinator. 



Tetragonal or pseudo-tetragonal: No axial ratio determined, as no pyramidal 

 planes developed. 



Forms observed: Prism (110) and base (001). 



Angles: 110 A 110=90; 110 A 001=90. 



Habit thin to thick tabular, by development of (001) and (110) (text figure 36); 

 in single crystals and in groups, often arborescent by growing together on the base or on 

 a pyramid; also in clusters, but without definite appearance of twinning. Some of the 

 large crystals were evidently composite, but did not show any appearance of twinning 

 when examined on edge in polarized light. 



Pleochroism faint, apparently abnormal; the absorption for the direction of greater 

 elasticity appears to be slightly greater than for the direction of less elasticity. Colors 

 are deep oxyhemoglobin red; somewhat paler for u>. 



Uniaxial, singly refracting on the base in parallel polarized light, and showing a 

 faint dusky cross in convergent light. Seen on edge the double refraction is very weak, 

 but is observable with the aid of the quartz wedge, etc. ; when it is seen that u> is the 

 direction of less elasticity and hence a> > s and the optical character is negative. The 

 fact that the double refraction is so weak would favor the suspicion that the crystals 

 are composite and really only pseudo-tetragonal, as is the case with some crystals in the 

 next species, Olor columbianus. 



FIG. 36. Olor buccinator Oxyheinoglobin. FIGS. 37, 38, 39. Olor columbianus Oxyhemoglobin. 



WHISTLING SWAN, Olor columbianus. Plate 10. 



The specimen was received from the Zoological Gardens at Washington 

 and was clotted and in a very putrid condition. The clot was ground up 

 with sand, etherized, and the liquid obtained oxidized by exposing it to 

 the action of pure oxygen. It was then centrifugalized, and slides prepared 

 as usual, the drops being allowed to become very concentrated before cover- 

 ing. In only two slides out of some two dozen prepared did crystals appear. 

 The crystals were rather dark, but were oxyhemoglobin. 



Oxyhemoglobin of Olor columbianus. 



Orthorhombic: Axial ratio a : b : 6 =0.9057 :!:<!; also pseudo-tetragonal by 

 homogeneous regular growth. 



Forms observed: Prism (110), base (001). 



Angles: 110 A lTO=8S (normals); 110 A 001=90. 



