938 THE JOHN DAT FAUNA. 



M. 



Interorbital width 0.043 



Width of muzzle above second premolar 0.018 



Length of superior molar series - - 0.051 



Length of fourth premolar 0.012 



Length of sectorial 0.016 



Length of first tubercular 0.008 



Width of first tubercular 0.015 



Width of second tubercular 0.0085 



The dentition is better displayed by a second specimen. This consists 

 of the middle portion of a mandibular ramus and anterior part of the max- 

 illary of a young animal. The teeth are not fully protruded and their 

 crowns are beautifully perfect on exposure. The principal cusps of the 

 inferior premolars present cutting edges, as does the median posterior lobe. 

 In both third and fourth there is a small conic heel posteriorly, but an ante- 

 rior basal tubercle on the fourth only. The sectorial is large and robust, 

 and the heel is short, with an absolutely median cutting edge. The first 

 tubercular is longer than wide, and presents a nearly median cusp in front, 

 which is joined to a low one on the internal border of the crown. 



The superior canine has an obtuse cutting edge on the anterior and 

 posterior borders of the inner side. The first (third) superior premolar is 

 near to it, and is rather large, displaying a median cutting lobe and low pos- 

 terior heel. The fourtli is similar but larger. 



Measurements of No. 2. 



M. 



Anteroposterior diameter of second superior premolar 0.010 



Anteroposterior diameter of third inferior premolar 0.013 



Width of base of third inferior premolar 0.0065 



Elevation of crown of third inferior premolar 0.010 



Diameter of inferior sectorial \ ~ „„, 



( anteroposterior v.u4i 



Width of first tubercular C'006 



Remarks. — The Enhjdrocyon stenocephalus is an aberrant member of 

 the family Canidce. Besides the generic characters already pointed out, it 

 presents numerous specific peculiarities. Especially to be noticed is the 

 arrangement of the parts between the postglenoid process and the occipital 

 cond3'le. These do not present striking affinities to any form outside the 

 Canidce, so far as I can ascertain. 



Restoration, etc. — Without limb-bones the general form of this species 



