314 



CRYSTALLOGRAPHY OF THE HEMOGLOBINS 



the horse-type on the base (text figure 393). The crystals are of all forms of the combi- 

 nation of prism and base; equidimensional, elongated on the prism or vertical axis, 

 and flattened in this direction or tabular on the base. Cleavage is prismatic. These 

 crystals appear later than those of the a-oxyhemoglobin and seem to develop at the 

 expense of the latter, but both were seen together. The ^-crystals begin as plates, flat- 

 tened on the base, but grow into equidimensional blocks or short prismatic ciystals 

 resembling rhombohedra; or, by suppression of one prism face which is attached to the 

 slide or cover, they become unsymmetrically developed on the prism. 



393 



FIGS. 389, 390, 391, 392, 393. Papio langhrldi 0-Oxyhemoglobin. 



Pleochroism is rather strong; a pale yellowish-red, 6 rather strong scarlet-red, 

 c deep red. Double refraction strong; on basal sections the extinction is symmetrical; 

 on edge views, looking along the ortho-axis, the extinction is 13 from the basal trace in 

 the obtuse angle. The orientation of the elasticity axes is a A a = 13 in the obtuse angle; 

 b=6; c A ^=6 30', in the obtuse angle. On the base, one brush of an interference 

 figure is seen with traces of the other, the brushes widely separated. The acute bisectrix 

 of the optic axes is the axis of least elasticity, Bx a =c, and the optical character is positive. 



The y-oxyhemoglobin, observed in P. babuin, P. sphinx, and P. anubis, 

 did not appear in the preparations from the blood of this species. 



CHACMA, Papio porcarius. Plates 98 and 99. 



The specimen was received from the National Zoological Park at 

 Washington, District of Columbia. Slide preparations of the blood were 

 made in the usual way. The crystals formed readily and were not dissolved, 

 but kept in good condition for more than a month, gradually passing by 

 paramorphous change into methemoglobin, but without loss of form or of 

 sharpness of angles. The first crystals to form were the a-oxyhemoglobin 

 plates; these were soon followed by the /3-oxyhemoglobin, which developed 

 into very large crystals and groups, and became the predominant crystal; 

 but the two forms appeared together in the same slide. The third form, 

 y-oxyhemoglobin, seen in some other species of Papio, did not develop in 

 this species. 



a-Oxyhemoglobin of Papio porcarius. 



Orthorhombic: Axial ratio not determinable. 



Forms observed: Macropinacoid (100), brachypinacoid (010), base (001). 



Angles: The angles between the pinacoids were measured and gave 90 in each case. 



Habit tabular, or long or short prismatic; the crystal consisting of the three pina- 

 coids only. Small crystals are square tables, or, by becoming equidimensional, they 

 look like cubes; others are elongated square prisms. The larger crystals are usually 

 tabular. Taking the orientation of the axes, not from the laminated habit, but on the 

 basis of the arrangement of the elasticity axes adopted with Papio langheldi, the crystals 

 become tabular on the basal pinacoid (text figure 394). The tabular face (001) shows 

 growth lines meeting at right angles and, in many cases, distinct piling of the crystals 



