686 



G. BUSK ON THE MAMMALIAN REMAINS FROM THE 



to be amply sufficient to identify the species to which it belonged. 

 In order to render the distinction more immediately evident between 

 this specimen and the corresponding vertebra of the common English 

 Fox, and at the same time to show how exactly it resembles the same 

 bone in the Arctic Fox, I have subjoined figures of the three 

 bones, in which it will be seen that, besides their considerable 

 difference in size from the larger, the two smaller vertebras correspond 

 with each other in all other respects. 



Figs. 1-3. — Second Cervical Vertebra of the Arctic Fox, recent and 

 fossil, and of the Common Fox. 



-Arctic Fox. 



Fossil Specimen. 



Fig 3. — Common Fox. 



a. Lower surface. 



b. Side view. 



The chief points of difference between the axis vertebra of the 

 Arctic and of the common Fox may be briefly stated to consist in : — ■ 



(a) The smaller size of the former *. 



(6) The slenderness and more abrupt divergence of the transverse 

 processes. 



(c) The much greater prominence of the median keel or carina on 

 the under surface of the centrum. 



(d) A difference, difficult to describe, but sufficiently obvious on 

 comparison, in the form of the anterior articular facets. 



* The specimen of common Fox taken for comparison is of small size, and it 

 forms part of tbe skeleton of a Fox killed in Warwickshire, in the College 

 Museum. 



