260 C. Stock — Cenozoic Mammalian Remains 



Depth of proximal end 35.2 mm. 



Width of distal end 34 



Digit 3, phalanx 2 



Greatest length 57.7 



"Width of proximal end 30 



Depth of proximal end 25.7 



Greatest width of distal end 29.5 



Digit 3, phalanx 3 



Greatest length 29 



Greatest width 19 



Greatest depth 18 



a, approximate. 



Muddy Valley Beds, Muddy Valley, Nevada. 

 Merychippus? , sp. 



A single incisor tooth, no. 24099, fig. 12, from locality 

 3550, resembles closely comparable teeth of Merychippus 

 in size. The specimen, apparently a lateral tooth, is worn 

 and quite small. In no. 24099 the posterior or lingual 

 enamel border is recurved slightly outward at the inner 

 side. 



Measurements of No. 24099 



Transverse width measured along worn occlusal sur- 

 face 10 nun. 



Anteroposterior diameter measured along inner side . . 7.5 



Alticamelusf or Procamelusf , sp. 



Remains of camels from the Muddy Valley beds are 

 also very incomplete. The principal specimen, no. 23917,, 

 fig. 10, from locality 3550, consists of an anterior cannon 

 bone with associated carpal elements and phalanges 

 of the digits. The materials unfortunately are badly 

 crushed and belong to a young individual. 



In no. 23917 the cannon bone is long and very slender^ 

 the latter character being especially noticeable when the 

 specimen is contrasted with the corresponding element 

 from the Panaca beds (compare figs. 8 and 11). The two 

 specimens are nearly of same length, but their propor- 

 tions are totally unlike. The differences noted in the 

 proportions of the two forms certainly indicate generic 

 separation. 



