1 48 Bulletin American Museum of Natural History. [Vol. XV I. 



are deceptive, on casual examination, and not real. He says : 

 "A very convincing explanation of the condition of some 

 skins of White Mountain Sheep, which might be described as 

 'dirty white,' is found in the following interesting statement 

 furnished me on this point by Professor Lewis Lindsay Dyche, 

 of the University of Kansas, based on extensive personal 

 observations in the Alaskan Mountains : 



" ' The White Mountain Sheep are a " dingy or dirty- white " 

 during the summer season only. This is particularly true 

 during the months of July and August. By the first of July 

 the animals have shed their long, thick coats of winter hair. 

 At this time they are almost naked, so to speak, the hair 

 being not more than from J- to } inch in length. The animals 

 frequent the sunny sides of the mountain ranges, and make 

 their beds in masses of shale rock, or on slopes where there 

 is more or less dirt. They frequently paw the rocks and 

 earth away so as to make a form large enough to sleep in. 

 These places become more or less covered with droppings. 

 Light snows and rains come, the earth is damp, and the ani- 

 mals get their hair stained until they become a ' ' dingy or 

 dirty-white." By the first of September the snows are falling, 

 and the animals have a fair coat of hair. They make their 

 beds in the snow, and gradually become white. I saw skins 

 that were white. The ones I got early in September were 

 nearly white, but not beautiful and snow-white like those 

 taken late in the fall and early winter. Pure white skins in 

 the hands of the Indians soon become soiled, and^dingy with 

 smoke.'" 



