MIMOMYS 377 



the young tooth there is a small fourth outer angle and in front 

 of it a rather wide and shallow fourth outer valley. On the side 

 of the crown this valley becomes rapidly narrower and shallower 

 as it descends, until it is represented by a mere groove, which may 

 or may not persist in the adult tooth. In the type (Forsyth 

 Major, op. cit., figs. 7 and 10a) this groove is represented 

 by a scar impressed upon a surface of bare dentine. Forsyth 

 Major has figured a right m^ (op. cit., figs. 23 and 16); which 

 he doubtfully refers to M. newtoni; I have no doubt that 

 this specimen should be referred to this species, and would remark 

 that the scale drawn beneath Forsyth Major's figure is too long. 

 Mehely has figured [op. cit., Taf. viii) two jaws from the 

 Hungarian Pliocene, one (Fig. 1) from Nagy-Harsany, the other 

 (Figs. 2 and 3) from Beremend. In these specimens the enamel 

 pattern of the Wj agrees closely with the English examples of 

 M. newtoni. The only difference is that no cement is shown in 



Fig. 103. — Mimomys newtoni Foi-syth Major. 

 Right />ij j'oung; crown and lateral views; " Clay-gravel," East Runton. 



the infolds ; but this circumstance is explained by Mehely (p. 221), 

 who says that cement was originally present, but, unaware of 

 its importance when he began his researches, he removed it 

 when cleaning the figured specimens. 



Newton has described two very important specimens from the 

 Upper Pliocene brickearth of Tegelen-sur-Meuse, which have since 

 been presented to the British Museum by Mr. and Mrs. Clement 

 Reid. These were referred by Newton to M. intermedins, but 

 after a careful study of the matter I have no doubt that they 

 should be referred to the present species. One of these teeth is a 

 very young left m^, lacking the posterior loop, which has been 

 broken oft", and having the cement spaces and pulp-cavities open 

 below (Fig. 99, is, iso). In this the third outer angle has no " prism- 

 fold," while the third outer valley is filled with cement and is 

 perfectly persistent. In front of the small fourth outer angle is a 

 fourth outer valley ; with a little more wear the imier part of this 

 valley would be converted into a quite ephemeral enamel " islet " ; 

 below the point of insulation a faint shallow vertical groove, 

 v.L. c c 



