234 



MEBISTIC VARIATION. 



[part I. 



Large Premolars. 



311. Putorius (labelled " Vison Horsfieldii"): at the place in which 

 the right lower posterior premolar ("j7 4 ") should stand there are two 

 such teeth at the same level. They are almost identical, but the inner 



-A 



Fig. 52. Putorius, No. 311, right lower jaw, ground-plan of teeth and profile 

 views of two teeth at the same level. Upper figure is the internal tooth. 



(upper in figure) is slightly the smaller (Fig. 52). B. M., 823, a. 

 312. Helictis orientalis, Java: having supernumerary two-rooted 

 tooth internal to and between p 2 and f£. This extra tooth is almost a 

 copy of if (Fig. 53). B. M., 824, a. 



Fio. 53. Helictis orientalis, No. 312. Surface view of upper jaw and a 

 representation of the right upper teeth as seen from inside. 



Molars. 



313. Putorius: Hensel, Morph. Jahrb., v. 1879, p. 540, states that he 

 has several skulls of Fcetorius putorius with an extra upper molar on 

 one side in a rudimentary condition. Giebel, Bronn's Kl. u. Ord., p. 

 18G, Taf. xv. figs. 1, 2 and 3, figures a specimen of "Putorius typus" 

 having a fairly well developed extra upper molar on each side making 

 m# instead of m\. Probably both these accounts refer to P. fcetidus. 



314. Lutra platensis: supernumerary molar on one side of upper jaw. 

 Such a tooth normally present on both sides in L. valetoni, a fossil 

 form. Von Heuglin, Nov. Act. Leop. Car. Cces., xxix. p. 20. Lutra 



