212 



CRYSTALLOGRAPHY OF HEMOGLOBINS OF THE UNGULATES. 



sectors meeting at a point in the center; sometimes, by irregularity of growth, 7 

 individuals are seen in the group. The following more detailed description will make 

 the arrangement plain. Suppose a fiveling, the members taken in cyclic order around 

 from 1 to 5. Nos. 1 and 2 twin on the orthopinacoid (100); 3 is twinned to 2 on the 

 hemiorthodome (10T) and to 4 on the orthopinacoid; 5 is twinned to 4 on the hemiortho- 

 dome which brings its orthopinacoid in parallel position with the hemiorthodome of 1, 

 thus completing the cycle. In each member of the twin the base forms one of the sides 

 of the pentagon. 



n\ 



164 



166 



168 



Fios. 164, 165, 166. Omi arlet Oxyhemoglobin. FIGS. 167, 168. Ovit ariet Reduced Hemoglobin. 



These twins are often seen terminating a long prismatic crystal and, as already 

 noted, they sprout out of the side planes of the long crystals, producing the banded 

 appearance seen in the photographs. 



Pleochroism is very strong; a nearly colorless, b moderately strong red, c very 

 deep blood-red. In the plates, the extinction is symmetrical on the base, and straight 

 on the aspect looking along a; on the (010) aspect, the extinction angle is 30 with the 

 prism edge. The long prismatic crystals show the same extinction as the plates. The 

 orientation of the elasticity axes is a A a = 6, b = b, c A <5=30. The axial plane is the 

 plane of symmetry, a is probably the acute bisectrix, but the interference figure was not 

 observed. The optical character is probably negative. 



Reduced Hemoglobin of Ovis aries. 



Orthorhombic: Axial ratio a : b : t 0.7813 :!:<!. 



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



Angles: Prism angle 110 A 1TO = 76 (normals); prism to base 110 A 001=99. 



Habit tabular on the base, the crystals consisting of a very short prism and the basal 

 pinacoid (text figures 167 and 168), the ratio of the length of the prism to the short diag- 

 onal of the base being about 1 : 5. The crystals occurred singly and did not appear to form 

 twins. They appeared rather sparingly in the slides about a week after the preparations 

 were made and seemed to show no tendency to dissolve on slight increase of temperature. 



Pleochroism is strong; fl nearly colorless, b deep red, c deep purplish-red; the colors 

 of b and c are nearly equal. Extinction is straight in all positions on edge and symmet- 

 rical on the base. The orientation of the elasticity axes is a=b, 6=<5, c=o. The plane 

 of the optic axes is the basal pinacoid and the acute bisectrix, Bx a =a. The optical 

 character is hence negative. 



BURRELL OR BHARAL, Ovis nahura. Plates 42 and 43. 



The specimen was received from the National Zoological Park at 

 Washington, and consisted of a small quantity of blood in the shape of 

 clots, with a small amount of liquid. It contained much foreign matter in 

 suspension. The blood was oxalated, treated with ether and centrifugalized 



