CRYSTALLOGRAPHY OF HEMOGLOBINS OF THE UNGULATES. 



207 



length on edge. The axial plane lies in the plane of symmetry and the orientation of the 

 elasticity axes is a A a = 18, b =b, c A = 18. The interference figure was not observed, 

 but from the character of the pleochroism it may be judged that the crystals are optically 

 positive. 



INDIAN ANTELOPE, Antilope cervicapra. Plate 37. 



The specimen was received from the Philadelphia Zoological Gardens. 

 The blood was partly in clots and somewhat putrid. It was ground with 

 sand and ether, and centrifugalized. After it had cleared, some oxalate 

 was added and the solution again centrifugalized. From the clear solution, 

 the slide preparations were made in the usual manner. Crystals formed 

 readily in the dried protein ring and along the edge of the cover. The 

 photographs were made on the following day. Examination with the 

 microspectroscope showed that the crystals were oxyhemoglobin. They 

 appeared quite insoluble, showing no tendency to dissolve on bringing the 

 slides into a warm room. 



,/ 



155 



156 



FIGS. 155, 156. Antilope cer- 

 vicapra Oxyhemoglobin. 



Oxyhemoglobin of Antilope cervicapra. 



Monoclinic: Axial ratio a : b : c =1.887 : 1 : c; /? = 71 45'. 



Forms observed: Unit prism (110), base (001). 



Angles: Prism angle on cross-section of prism 110 A 1TO = 

 58 20'; angle of prism traces on the base, edge 110-001 A 1TO- 

 001 = 56 (about); angle of prism edge to base 110-110 A 001 = 

 71 45' (normals) =/?. 



Habit prismatic, elongated on the vertical axis, the acute 

 prism obliquely terminated by the base (text figure 155). In many 

 crystals the prism appears to be flattened on two of the opposite 

 faces, becoming lath-shaped. The faces of the prism are vertically 

 striated, and there is an appearance of cleavage, parallel to the 

 prism faces. The crystals are large, and the length is very great in 

 proportion to the width. When seen in the aspect looking along a, 

 the termination of the prism frequently appears to be square. The 

 crystals grow in groups and slightly divergent tufts. Twins on the 

 prism face as the twin plane were noted; they were rare (text figure 156). They seemed 

 to be usually juxtaposed twins, but a few interpenetrant twins were seen. 



The color is oxyhemoglobin red, but the pleochroism is strong and the crystals 

 look light or dark according as the aspect presented is normal to a or parallel to a. The 

 colors are: a pale pinkish, 6 red, c deep red. Extinction seems to be parallel to the 

 prism edges in all positions of the prism normal to the c axis, and symmetrical on the 

 cross-sections. The orientation of the elasticity axes is a A a = 18 15', in the obtuse 

 angle; b=6; c=i; the plane of the optic axes is hence the plane of symmetry and the 

 angle between c and c is 0. Looking along a, traces of the interference brushes are seen, 

 but pass far out of the field; this would seem to indicate that the axis of least elasticity 

 is the acute bisectrix, Bx a = c, and the optical character is positive. 



From the straight extinction, it looks as though this might be an orthorhombic 

 crystal with one pair of macrodome faces developed; but such symmetry as the crystals 

 show is plainly monoclinic. 



REDUNCA ANTELOPE, NAGOR, Cervicapra redunca. Plate 38. 

 The blood was from a specimen of the nagor that died in the New 

 York Zoological Gardens, and was received from New York in good condi- 

 tion. It was oxalated, laked with ether, and centrifugalized; the slide 

 preparations were made in the usual manner. The crystals formed readily, 



