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SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 6l 



Mr. C. W. Gilmore, who led an expedition into Alaska in 1907, 

 reported (Smithsonian Misc. Coll., Quarterly Issue, Vol. 2, p. 31) 

 that fossil horse remains, a single bone or two, now in the U. S. 

 National Museum, were found on the Kowak, or Kobuk, River 

 (fig. 1 (8)). He also ascended the Nowitna River, a southern 

 affluent of the Yukon, a distance of about 180 miles and found, on 

 the sand bars, remains of horse, mammoth, extinct bison, etc. 

 (fig. 1 (9)). Mr. Gilmore further reported the finding of Equus 

 remains along the Palisades on the Yukon (fig. 1 (10)). These 



Fig. 4.— Left last lower molar, No. 866, U. S. Nat. Mus. X Ya- 



Fig. 5. — Left lower second premolar, No. 2645, U. S. Nat. Mus. X Ya- 



Fig. 6. — Left lower tooth, probably first molar, No. 2645, U. S. Nat. Mus. X Ya- 



Fig. 7-— Left lower third molar, No. 2645, U. S. Nat. Mus. X Ya- 



Fig. 8. — Left lower tooth, premolar or molar, No. 2645, U. S. Nat. Mus. X Ya- 



Palisades begin about 35 miles below Tanana. The materials secured 

 by Mr. Gilmore included no teeth and are specifically indeterminable. 

 In the U. S. National Museum is a part of the left side of the 

 lower jaw of a horse and in it is found the last molar. The catalogue 

 number is 866. In an older catalogue the information is given, under 

 the number 6563, that this jaw was collected in the region of Ram- 

 part (fig. 1 (11)). It was secured by Dr. William H. Dall, who tells 

 the writer that the discoverer of the jaw was Mr. J. Lockhart, an old 

 trapper in the employ of the Hudson Bay Company. The tooth is 

 worn down to a height of about 45 mm. The length of the grinding 

 surface (fig. 4) is 37 mm. ; the width in front is 16 mm. This is 

 greater by about 3 mm. than the width of the same tooth in the type 

 of Equus niobrarensis; but that tooth may not have yet reached its 

 full width. No other differences of importance are observed. 



