MAMMALS. 



283 



Mr. C. L. McKay. They comprise a skin of an adult male and one of an adult fumale and the 

 horns and scalp of a second female. In the following table the proportions of Mr. Nelson's speci- 

 mens are compared with those of a specimen of the normal variety from Montana : 



Mr. McKay's specimens, from the Chigmit Mountains, present the following proportions. 

 13652 and 13653 are flat skins : 



Nos. 



Measurements. 



Length from point between the horn-cares to base of tail 



Length from point between the horn-cares to extremity of nose. 



Length of horn around curves 



Circumference of born at base 



Distance between the points of the two horns 



No. 13653. 



cT adult. 



Cm. 

 139.5 



94.5 

 28.5 

 58.5 



No. 13652. 



5 adult. 



No. 14083. 



Horn's ?. 



If any conclusion is warranted by these few data, it is, perhaps, that the Alaskan sheep is con- 

 siderably smaller than its southern relative, and that it carries to the extreme the variations in the 

 shape of the horn (extension and decrease in diameter at the base), observable in northern exam- 

 ples of the normal variety, 0. canadensis {typicus). 



It would be interesting to know the southern limit reached by Ball's sheep.* 



List of S2)ecimens. 



Biographical notes. — The discovery of this fine animal is one of the most valuable results of my 

 work in the north. It is limited to the higher mountain ranges of the Territory, except in the 

 extreme northern portion, within the Arctic Circle, where it ranges down nearly to the sea-level. 

 Following the main range of the Eocky Mountains it is found in the southeastern part of the 

 Territory and north along these mountains to the point whe.Te the chain swings to the west, and 

 along its western extension, known as the Alaskan range, it is numerous nearly to the head of 

 Bristol Bay. In this portion of the mountains Ball's Sheep is found upon the Pacific slope as \vell 

 as on the northern side. I could not learn of its occurrence on the peninsula of Aliaska, although 

 some individuals may be found there. 



' See a letter by Lieutenaut Allen on the Eumiuants of the Copper River Region in Science, vol. vii, p. £7. 



