OF THE DOGS, WOLVES, AND FOXES. 



277 



frozen in the refrigerating plant until examined; it was in good condition, 

 and evidently was collected when the animal was but recently dead. The 

 second specimen was somewhat putrid and thick; and had probably been 

 taken some time after death. Both had been collected in oxalate, in our 

 regular collecting tubes. The two specimens were treated in the same man- 

 ner; laked with ether and centrifugalized, and from the clear solution thus 

 obtained the slide preparations were made in the usual way. The blood 

 crystallizes very readily, and within a few hours after the preparations were 

 made the slides were in condition for examination. The stale blood crys- 

 tallized rather faster than the fresh specimen, due no doubt to its being in a 

 more concentrated condition. The portion of clear solution remaining in 

 the tube after the slides were prepared from this stale specimen became a 

 mass of crystals within 2 hours after the preparations were made. The 

 crystals keep well and show no tendency to dissolve in the solution. They 

 were oxyhemoglobin in the case of the second sample of blood, which was 

 the one from which the measurements were obtained on which the crystal- 

 lographic constants were determined. The other sample appeared to have 

 been converted into the acid form of metoxyhemoglobin. Its crystallo- 

 graphic constants were the same as those of the second specimen, so far as 

 they were recorded, but the habit of growth of the crystals was somewhat 

 different. 



Oxyhemoglobin of Vulpes lagopus. 



Orthorhombic: Axial ratio a : 6 = 1 : 0.4265. 



Forms observed: Unit prism (110), macrodomes (101), 

 (405). 



Angles: The prism angle was not obtained; macrodomes 

 101 A TO 1 = 46 12' (average); 405 A 105=56. 



Habit long prismatic on the vertical axis, the crystals at 

 first almost capillary, but later becoming stouter, and even short 

 prismatic in the case of the second specimen. The ratio of length 

 to thickness of the larger normal crystals was about 20 : 1 in the 

 first specimen and 10 : 1 in the second (text figure 315). The 

 crystals do not show very much tendency to form large parallel 

 growths, but are single crystals, in which the tendency to par- 

 allel growth so common in this genus is only indicated by verti- 

 cal striation on the prism and flattening on the macropinacoid. 

 This produces rather flattened lath-shaped and striated crys- 

 tals, which nearly always present the flat aspect, and hence are 

 square on the end which is cut by one of the macrodomes. 

 Usually only one of these domes develops on a single crystal, but sometimes both may be 

 seen in the same crystal. The unit dome seems to predominate. 



The crystals from the first specimen, which appeared to be metoxyhemoglobin, 

 showed a decided tendency to grow into circular or spherulitic groups of crystals, radiat- 

 ing from a common center; and this was particularly true of the crystals that formed 

 in the protein ring; those from the second specimen did not show this tendency, but 

 were usually single crystals matted together into a felt, and occasionally grouped as 

 though twinned on a pyramid. 



Pleochroism is rather marked; for the oxyhemoglobin the colors were: a pale red- 

 dish or pinkish; 6 and c nearly equal, varying from paler to deeper red according to the 

 thickness. Looking along a, the double refraction was rather weak; along b it was very 

 strong. Extinction was straight in all aspects. No interference figure was made out, 



316 



FIG. 315. Vulpet lagopus Oxy- 

 hemoglobin. 



FIG. 316. Urocyon cinereoargen- 

 teut Oxyhemoglobin. 



