OF THE LEMURS, BABOONS, AND MAN. 



319 



feet, and no trustworthy measurements could be made. These crystals 

 dissolved at room temperature, but rather slowly; the examination could 

 be carried on with a low power for 20 minutes before the melting became 

 very noticeable. Under a high power the acicular rods showed rounded 

 ends, evidently indicating incipient solution. No satisfactory optical 

 characters, beyond the straight extinction, were observed; the solution 

 was so deeply colored, and so near the color of the crystals, that the pleo- 

 chroism was not observable. 



Reduced hemoglobin of Homo sapiens africanut. 



Monoclinic: Axial ratio not determined. 



Forms observed: Clinopinacoid (010), orthopinacoid (100), base (001). 



Angles: Orthopiuacoid to base, 100 A 001 =81 30' =angle /?; clinopinacoid to base 

 010 A 001 =90. 



Habit tabular on the clinopinacoid or plane of symmetry (text figures 410 and 411) ; 

 the tabular crystals almost rectangular plates. The crystals show a ratio of thickness 

 to length of the rhomboidal edge of about 1 : 5. The crystals formed rather sparingly 

 in the slides in which the oxyhemoglobin crystals had been observed, also in other slides 

 prepared from stale human blood, and in slides of fresh blood that had been kept 

 sealed for a number of days. In each case the crystals were of the same type, the squarish 

 tabular crystals above described. The short prisms and rhombic plates described as 

 orthorhombic by von Lang with 54 6' prism angle, and the orthorhombic crystals with 

 prism angle of 73 to 73 35' as described by Funke were not observed. The crystals 

 were often so large as to be interfered with in their growth by the slide, but showed a 

 tendency to aggregate into groups, so that the entire outlines of the individual crystals 

 could not be made out in many cases. 



Pleochroism is rather strong; a nearly colorless to pale purplish, b dark purplish 

 red, c dark red. Double refraction is strong; the extinction of the plate on edge views 

 is straight in all aspects; and on the flat view, or the plane of symmetry, the extinction 

 is nearly or quite parallel to one edge of the plate, but it makes an acute angle with the 

 other edge. Orientation of the elasticity axes is a =6; bAa=8 30', in the acute angle; 

 c A 6=0. The interference figure was not observed. 



TABLE 50. Crystallographic characters of the hemoglobins of the Primates. 



* Traces of the prism on base. 



