In the Norfolk Forest-hed^ Cromer. 441 



and have, as appeared to me at first, a much, less flattened form, 

 presenting in section a full round outline on that side which forms 

 the outer edge of the tooth's curvature. A comparison of specimens 

 of Megalosaurus teeth with this Norfolk fragment, leaves no doubt 

 as to their complete distinctness. On the other hand, the fragment 

 agrees in detail, as well as in general appearance, with the right 

 upper canine of Machairodus. The tapering of the tooth corres- 

 ponds closely with that of a large-sized Machairodus canine, as 

 shewn in the figure, one side of the tooth being a little more convex 

 than the other. The serrated edges do not run vertically, so that 

 the plane passing through them would divide the tooth into two 

 unequal parts (see section Fig. 3) ; but, as is observable in Machai- 

 rodus, the opposite serrated edges are not parallel to one another, 

 but are curved — one slightly inwards, the other outwards. The 

 enamel on both surfaces is longitudinally split and cracked, exactly 

 in the same manner as it is on MacEnery's specimen from Kent's 

 Hole. Therefore, small though this fragment is, it carries, suffi- 

 ciently clearly marked on it, the evidence of the ownership of 

 Machairodus. 



The specimen is too incomplete to make any discussion of specific 

 characters useful. As to its geological age, there is every pro- 

 bability that it came out of the Forest-bed, whether contemporaneous, 

 in the period represented by that accumulation, with the recognized 

 Forest-bed Fauna, or not. The specimen is of a black colour ex- 

 ternally, of a deep brown on the fractured surfaces, and was picked 

 up on the shore between high- and low- water, amongst the debris of 

 the Forest-bed, 



Whilst having the good fortune to add this interesting carnivor 

 to the list of Forest-bed mammalia, I cannot let the opportunity pass 

 of mentioning — what, indeed, has been recognized by those working 

 at this deposit at home, but not by all writers — that Mastodon has 

 not been found in the Forest-bed ; and, that even were fragments 

 of that genus to occur, we might have to regard them as derived 

 from accumulations of an earlier period, just as it is possible, though 

 not probable, that this fragmentary Machairodus canine may have 

 been derived, 



EXPLANATION OF PLATE XVI. 



Eig. 1. Side-view of rigbt upper canine of ilachairodus. 



[The shaded parts of Figs. 1 and 2 represent the Cromer Forest-bed speci- 

 men ; the outlined entire canine is copied from the cast of a French speci- 

 men of Machairodus cultridens, Cuv., with the curvature of which the 

 Norfolk fragment closely agrees. The outline of M. latidtiis, Owen, from 

 Kent's Hole, tapers more rapidly than the Norfolk specimen, indicating a 

 much shorter canine. — Edit.] 

 Fig. 2. Front-view of right upper canine of Machairodus, showing the curvature of 



the serrated edge of the tooth. 

 Fig. 3. End-view of Mr. Jarvis's specimen, showing the serrated edges which divide 

 the tooth into two unequal parts (/ anterior, i posterior edge of tooth). 

 Fig. 4. A portion of the serrated margin of the tooth enlarged. 

 c. c. The part ahovc this line is enclosed in the jaw, the other letters show the cor- 

 responding parts in Figs. I and 2. 



