4r)2 ME. E. T. NJ-nVTON OX XEW MAMMALS FEOM 



lower part of the lied Crag (nodule-bed), near Boyton. This 

 tooth being unlike anything hitherto known from the Crag, was 

 awaiting determination, when Mr. Lydekker saw it and, recognizing 

 its resemblance to the tooth of Ailuvus fv.lgens, kindly lent me a 

 skull of this recent species for close comparison ; it is to Mr. 

 Lydekker, therefore, that we are indebted for the first identification 

 of this tooth. On comparing the specimen with the left, upper, 

 first true molar of Aihirns fnlgeas (see PI. XYIII. figs. 10 a, 10 ft), 

 the resemblance between them in the form and position of all the 

 cusps and tubercles is most striking. On the outer side are two 

 cusps (a, b, the front one being the larger of the two), which have a 

 strong ridge running down their anterior and posterior surfaces : a 

 third cusp, c, placed within and near to the hinder one, is flattened 

 on the outer aspect and rounded on the inner, while ridges pass from 

 its summit downwards and outwards towards the outer cusp. The 

 inner portion of the crown is occupied by a cusp, d, larger than either 

 of the others, from w^hich a ridge extends forwards and outwards to 

 join a large tubercle, i, situated upon the front of the tooth. This 

 tubercle, in common with all those now to be mentioned, forms part 

 of a strong cingulum, which may be traced round the crown. On 

 the outer side of the tooth are three large tubercles, one (2) before, 

 one (4) behind, and one (;^) between the two cusps ; and at the back 

 of the tooth, between the outer and inner cusps, is another smaller 

 tubercle (5). The inner part of the tooth is rounded, with the cin- 

 gulum particularly well marked, and towards its hinder part deve- 

 loped into one or two small tubercles (b). In all these particulars the 

 fossil and recent teeth are precisely similar ; with only such trifling 

 differences as might be due to individual variation, the greatest 

 being the absence, in the recent tooth, of the small tubercle marked 5 

 in the fossil. 



It will be remembered that the lower tooth of Ailurus anglieus 

 was described as about one third larger than that of A. fulgens (i. e. 

 70 mm. and 48 mm.): and the upper tooth, now described, has the 

 same proportion to the first upper molar of that species ; its length 

 from before backwards, however, is greater in proportion to its 

 width, as will be seen by the following measurements : — 



A. fulgens. A. anglmts. 

 Upper m. 1, length from before 



backwards 9-5 14*5 millim. 



Upper m. 1, width 11-5 14-5 millim. 



The height of the crown and cusps in the fossil is proportionately 

 less than in the recent form, and in this particular corresponds with 

 the lower tooth described by Prof. Boyd Dawkins. Another peculiarity 

 of the upper tooth is that the bases of all the cusps are strongly 

 grooved or striated, a character which is only seen to a very slight 

 extent in A. fulgens. 



This tooth is of itself sufticient to establish the presence in the 

 Red Crag of a species closely allied to Ailurus fulgens ; and, as it 



