70 PLEISTOCENE MAMMALIA. 



strongly with the large size of the corresponding tubercle of HyeRua spelcea. The anterior 

 blade which forms the primary cone of the tooth [a) is the higher. A small rounded 

 ridge passes from its summit to the tubercle (/). Posteriorly, its trenchant edge declines 

 in height to the point where it is divided by a cleft from the posterior blade (c). The 

 latter forms a trenchant waved horizontal edge, situated at an angle to the blade (a) 

 which is very obtuse externally ; below the cleft, the external side is hollowed out, so 

 that the surface of the crown at this point is horizontal. The internal surface of the 

 tooth is flattened from the tubercle (/) backwards, and is at a moderately early age worn 

 away by the friction of M 1. A tooth in this condition is represented in fig. 13. The 

 cingulum is well developed, forming anteriorly, in most of the larger specimens, a well- 

 developed cusp on the outer edge of the cusp {h) ; this may be taken as the rudiment 

 of an " accessory " cusp (d), which assumes much larger proportions in DM3 of 

 Felis. Half the cone (a) and the whole of (c) are supported by a fang of flat- 

 tened oval section, and triangular or trapezoidal in outline, and the other half of 

 (a), and {d), and (d), by a smaller one, subcylindrical, and nearly straight, diverging at 

 a considerable angle from the first, and, as before stated, the tubercle (/) by a still 

 smaller fang, similar, and of equal length, and generally connate Avith the second, and 

 sometimes united to it throuoh its whole length. The extreme variations in size that 

 we have met with are shown in our plates of the smaller skull (Pis. VI and VIII, and in 

 PI. XI, figs. 1, 12, 13). 



Molar 1. (Fig. 14). — VV^e have seenbut one specimen of the true molar of Felis spelma. 

 It is from Bleadon. It is elliptical in outhne, the long axis of the ellipse being trans- 

 verse ; it is supported by two connate and confluent fangs ; but we have met with alveoli 

 which indicate that they are sometimes connate only. This specimen is much worn, as 

 is generally the case with the corresponding recent teeth. We do not, therefore, give a 

 more particular account of the tooth than that given in our Introduction to the Dentition 

 (p. 66) ; but refer to our figures, which give the general appearance. The alveoli are 

 represented in PI. XI, fig. I, and in PI. VIII, at the postero-internal angle of PM4. 



A comparison of the upper permanent dentition of F. spelcBa with that of lion and tiger, 

 has compelled us to infer that there are no points of difference of specific value between 

 them ; the largest teeth of F. spelaa are larger than those of the largest living lions and 

 tigers ; but they form a regularly graduated series from the smallest to the largest 

 form. The smallest teeth of F. spelcea, indeed, are far smaller than the average of the 

 living animals. Those already alluded to from the Gower cavern are only to be matched 

 by the very smallest leonine and tigrine teeth. Dr. Schmerling long since determined 

 that the character of the absence of PM 2 , depended on by MM. Goldfuss and Cuvier as 

 characteristic of Felis spelaa, was a simple variation, which is also, as we have before 

 stated, common to lion, tiger, and other Feles. 



^ 2 ^. Permanent Dentition of Lower Jaw (Pis. I, VI, and XII). — The dentition of 



