208 Mr. O. Thomas on small Mammals 



These specimens agree sufficiently closely with Philippi's 

 figwre and description of O.ri/mi/cferus valdivianus to render it 

 fairly certain on geographical grounds that they should be 

 referred to that animal. The question of its generic name is 

 dealt with below. 



" Live among the roots of fallen trees. Make burrows in 

 the earth like tuco-tucos." — E. B. 



15. Geoxus fossor, sp. n. 



(?.178, 194. Maiten, W. Chubut. 700 m. 



" Found under bushes (' retamos '), where they make holes 

 with small hillocks over them, just like tuco-tucos. The 

 similar mice from Nahuel Huapi do not make such hillocks.'* 

 —E.B. 



The six long-clawed Murines placed under these two 

 headings have enabled me to make a fresh examination of 

 the relationship they bear to my JSotiomys edwardsi, to the 

 genus Oxymycterus, and to the far southern species that have 

 been referred to the latter. 



I have to confess that Dr. Allen's assertion that his Oxy- 

 mycterus microtis (to wliich these specimens are closely allied) 

 had nothing to do with Notiomys proves to be entirely correct, 

 my supposition to the contrary being wrong. Thanks to the 

 kindness of Prof. Trouessart, I have been privileged to 

 re-examine the type-skull of JSlotiomys edwardsi, and so am 

 able to base my opinion on a firm foundation. 



Of pertinent specimens we had previously only the two 

 examples, adult and young, from Koslowsky mentioned in 

 1903*, which, without sufficient reason, I assumed to be 

 both of the same species. The young one (whose skull was 

 crushed) being certainly Notiomys^ and the other closely 

 agreeing with " Oxymycterus'^ microtis, KWqu, the generic 

 identity of the two seemed to follow. 



But study of the present valuable accession shows that the 

 two Koslowsky animals are really diflferent — the young one 

 being Nutiomys edwurdsi, Thos., and the adult the species 

 described by Dr. Allen. 



On comparing now the good skulls of the mole-like animals 

 related to " Oxymycierus^' microtis in Sr. Biidin's collection 

 with the type-skull of Notiomys, I can confirm all tiiat 

 Dr. Allen t has said as to their essential distinctness. In the 

 former the skull is long and narrow, with long muzzle, smooth 



* Ann. & Mag. Nat. Hist. (7) xii. p. 243 (1903). 

 t Mamm. S. Pat. pp. 81-85, illustrated by figures of skulls, pi. ix. 

 (1905). 



