270 



CRYSTALLOGRAPHY OF THE HEMOGLOBINS 



302 



304 



303 



usual. The blood crystallized very readily, and the crystals showed no 

 tendency to dissolve in the solution. They were brownish in color, and the 

 spectroscope showed them to be metoxyhemoglobin. Later, a sort of second 

 crop of crystals appeared, of a somewhat different habit; but evidently 

 the same material, and with the same axial ratio. The morphological 

 characters of these crystals, including the angles, compare very closely 

 with those of other species of Canis, and evidently this metoxyhemoglobin 

 crystallizes much as the oxyhemoglobin does in this species, as is found to 

 be the case in other genera where both substances were observed in one 

 species and could be directly compared. 



Metoxyhemoglobin of Canis lupus mexicanus. 



Orthorhombic : Axial ratio a : b : c =0.6576 : 1 : 

 0.2863; a : c =1 : 0.4272. 



Forms observed: Prism (670), macrodomes (101), 

 (403). 



Angles: Brachy-prism angle 670 A 670 = 75 ; unit 

 prism (computed) 110 A TlO = 66 40'; macrodome 

 403 A 303=53; macrodome 101 A 101 (computed) 

 46 16'; measured roughly as 46. 



Habit long prismatic on the vertical axis (text 

 figures 302 and 303), the crystals as they increase in 

 size becoming strongly striated, due to composition of 

 many individuals in parallel growth. Capillary crystals 

 not so common as is usual in the Canidcc, but the thicker 

 crystals rather long in proportion to the thickness, with 

 a ratio of length to thickness ranging from 50 : 1 to 15 : 1. 

 The second-crop crystals are proportionately longer, and 

 many of them have a ratio exceeding 100 : 1. Among these rod-like crystals one or 

 two oblique sections of the prism (670) were seen developed as plates. The crystals of 

 the first crop showed a decided tendency to arrange themselves in groups, radiating 

 in all directions from a center; or frequently the rods would develop brush-like ends, 

 due to the same tendency to form divergent groups. In the second-crop crystals, this 

 tendency to form brush-like ends was especially pronounced; and they also formed 

 various tufted arborescent groupings, but without producing the circular radiating 

 clusters found so commonly in those of the first crop. The long, slightly divergent tufts of 

 the second-crop crystals, and the spherulitic radiating groups of the first crop, arc charac- 

 teristic of this species ; as are also the particular forms that are present, the prism (670) 

 and the dome (403). The unit macrodome was seen in crystals from a second preparation 

 from the same blood, and probably also the unit prism, but this last was not measured. 

 Pleochroism is not very marked, as the colors are not bright; it is quite noticeable, 

 however, and in some positions rather strong; the colors are shades of brownish, as 

 follows: a pale brownish, 6 deeper brownish, c deep brown. Double refraction is fairly 

 strong and extinction is straight in all aspects normal to the prism, and symmetrical on 

 cross-sections. The orientation of the elasticity axes is a=a, b=b, c = t. The interfer- 

 ence figure was not observed, but the relative elasticities appear to indicate that the 

 axis of greatest elasticity is the acute bisectrix, Bx a =a, and hence the optical character 

 is negative. 



COYOTE OR PRAIRIE WOLF, Cam's latrans. Plate 74. 



The specimen of blood was received from the National Zoological 

 Park at Washington, District of Columbia. The blood was stale, but not 

 putrid. It was laked with ether and centrifugalized for several hours; 



FIGS. 302, 303. Canis lupus mexlcanui 



Metoxyhemoglobin. 

 FIG. 304. Canif latrant Oxyhemoglobin. 



