OF THE DOGS, WOLVES, AND FOXES. 



269 



CROSS BETWEEN COLLIE DOG AND COYOTE, Canis familiaris AND Canis latrans. 



Plate 73. 



This specimen of the blood of a hybrid coyote was from an animal 8 

 years of age that was killed fighting with the other coyotes with which it 

 was confined; and was received from the Zoological Garden at Lincoln 

 Park, Chicago. The blood was not clotted; it was dark purplish in color 

 and quite putrid. It was ether-laked, mixed with an equal volume of 

 50 per cent solution of egg-white, and centrifugalized. From the clear 

 solution thus obtained the slide preparations were made in the usual man- 

 ner. The blood crystallized very readily, and inside of 2 hours after the 

 slides were covered satisfactory photomicrographs were obtained. The 

 crystallization was very complete, and the crystals showed no signs of 

 dissolving. The crystals were oxy hemoglobin. 



IT 

 Oxyhemoglobin of cross between C. familiaris and C. latrans. 



Orthorhombic: Axial ratio a : b : 6 =0.6619 : 1 : 0.2912; 

 a : t =1 : 0.4400. 



Forms observed: Unit prism (110), macrodome (101), (706), 

 base (001). 



Angles: Prism angle about 67, not measured exactly; macro- 

 dome angle 101 A 101=47 30'; macrodome 706 A 706=54 30'; 

 prism to base 110 A 001=90. 



Habit medium and long prismatic to capillary; the first-formed 

 crystals are trichites without much dimension, aside from length; 

 these soon increase in diameter, and become measurable crystals, 

 with a ratio of length to thickness of 20 : 1 or less (down to 10 : 1) 

 (text figure 300) ; some of the first-formed crystals, even, show such 

 relative dimensions. The crystals of large size show, usually, parallel 

 growth on the prismatic axis, producing the usual groups of two, side 

 by side, and united on the brachypinacoid; but much more often 

 they form irregular groups in parallel growth, looking like bundles 

 of crystals; and these, especially, grow in such a manner that the dome faces are sup- 

 pressed and a pseudo-basal pinacoid develops. These groups appear cut off square on 

 the ends by this apparent base (text figure 301). Whether the real basal pinacoid 

 actually occurs, or whether the apparent base is always this pseudo-plane, could not be 

 determined. Both the capillary and the stouter crystals are found growing in irregularly 

 radiating tufts, as is common in the dog crystals. Twins were only doubtfully observed; 

 the apparent twins seemed to be on the pyramid. 



Pleochroism is rather pronounced; a nearly colorless, 6 rather strong red, c rather 

 deep red; but the colors of b and c are not so very different. Double refraction is strong 

 and extinction straight in all side views. In convergent light, looking along the brachy- 

 axis, the biaxial interference figure is seen, with widely separated brushes, and the orien- 

 tation such that the plane of the optic axes is the brachypinacoid. The orientation of 

 the elasticity axes is a=a, b=6, c = 6. The acute bisectrix of the optic axes is the axis 

 of greatest elasticity, Bx a = a, and the optical character is negative. 



GRAY WOLF, Canis lupus mexicanus. Plate 74. 



This specimen was received from the Philadelphia Zoological Gardens. 

 The blood was of a brownish color and was rather thin and watery. It 

 was oxalated and ether-laked and then centrifugalized for several hours. 

 From the clear solution thus obtained the slide preparations were made as 



300 



FIGS. 300. 301. Oxy- 

 hemoglobin of Cross of 

 Collie and Coyote. 



