A NEW GENUS OF EXTINCT MUSCARDINE RODENT. 



209 



11. On a new Genus of: Extinct Muscardine Rodent from 

 the Balearic Islands. By Dorothea M. A. Bate *, 

 Hon. M.B.O.U. 



| Received April 9, 1918 ; Read May 7, 1918.] 

 (Plate I.t and Text-figs. 1, 2.) 

 Index. 



Systematic: Pasre 



Mypnomys, gen. n 210 



H. mahonensis, sp. n 218 



II. morpheus, sp. n 219 



During a second visit to Mallorca in 1910 in search of ossiferous 

 deposits a few rodent remains were obtained ; the following year 

 further researches were carried out in Menorca by means ot a 

 grant from the Trustees of the Percy Sladen Memorial Fund, and 

 here similar remains were found to be somewhat more plentiful, 

 occurring in several fissures in the Miocene limestone. A de- 

 scription of the deposits from which the collection was obtained 

 has already t been published J. A first cursory examination 

 of the specimens led me to suppose that they represented large 

 forms of Eliomys§ or Leithia\\. Since then a number of spe- 

 cimens from Menorca have been developed from the hard matrix 

 in which they were embedded, ancl all have been carefully 

 examined, with the result that it is found that they cannot be 

 included in any genus with which I have been able to compare 

 them. The examples from the two islands differ considerably in 

 size, those from Menorca being the larger, and they are probably 

 specifically distinct: in this connection it is interesting to remember 

 that, after the examination of a very large quantity of material, a 

 similar variation in size was found to obtain in Myotragas%. 

 This seems to point to a longer period of isolation in Menorca, 

 the most easterly and probably the first of the group to be 

 separated from the mainland. 



All the remains obtained are now in the collection of the 

 British Museum (Natural History). No complete skulls and 

 only a few limb-bones were procured, but it will be seen from 

 the descriptions of the specimens given below that the Balearic 

 genus should undoubtedly be included in the Muscardinirlas. 

 The specimens to be described are intermediate in size be- 

 tween the largest recent forms and the extinct Leithia from 

 Malta, and show a number of points of resemblance both to 

 the recent Eliomys and to the Maltese Leithia, but at the same 

 time differ to an equal extent from both these genera. The 



* Communicated by Dr. A. Smith Woodward, F.R.S., F.Z.S. 

 f For explanation of the Plate see p. 222. 

 % Geol. Ma?. [6] vol. i. 1914, pp. 337-45. 

 § Ibid. p. 100. 



i| Proc.Zool.Soc. 1916. p. 424. 



% See Andrews, Phil. Trans. Roy. Soc. ser. B, vol. 206, 1915, p. 301. 



