i 9 2 APPENDIX 



a distinct species of the sheep family, first determined by Mr. 

 E. W. Nelson of the United States National Museum and 

 by Mr. Nelson, in 1883, were named Dall's sheep in honor 

 of Mr. W. H. Dall. Since then they have been frequently 

 observed and studied by various naturalists, but it is chiefly 

 to the keen, patient, and persistent observation and studies 

 of Mr. Charles Sheldon over a very considerable period that 

 we are so greatly indebted for the enrichment and fullness 

 of our knowledge concerning the different species of .north- 

 ern sheep. 



In his original description of Ball's sheep in Volume VII, 

 pages 12, 13, 1884, of " Proceedings of United States 

 National Museum," Mr. Nelson states: "This form can 

 be recognized at once by its nearly uniform dirty white 

 color. . . . The dinginess of the white over the entire body 

 and limbs appears to be almost entirely due to the ends of 

 the hairs being commonly tipped with a dull, rusty speck. 

 On close examination this tipping of the hairs makes the 

 fur look as though it had been slightly singed." Mr. 

 Charles Sheldon, preeminently an authority on northern 

 sheep, speaks of this " dinginess " as being not a true pig- 

 mentation, but due simply to the sheep's pellage being dis- 

 colored in summer time from contact with the soil and dirt 

 on the mountains. Mr. Sheldon frequently speaks of the 

 Dall as " stained white sheep," and their summer pellage as 

 being " badly stained," while their winter pellage is pure 

 white. 



Without any intention of even suggesting that the Dall 

 sheep observed and reported by Mr. Nelson and Mr. Shel- 

 don had other than dingy white summer pellage, since both 

 these scientists are accurate in their observations and have 



