76 Dtt. A. SMITH WOODWVltU OX REMAINS OF [Jan. 23, 



sized species of Arctotherium must therefore have survived until 

 the human period in Southern Patagonia l . 



Onohippidium saldiasi. 



A horse is represented in the collection by an upper molar 

 (no. 55), a fragment of premaxilla with two incisors (uo. 56), 

 an imperfect atlas (no. 57), and two well-preserved hoot's 

 apparently of a foetus or perhaps of a newly-born animal (no. 5^). 

 Of these remains only the upper molar is capable of satisfactory 

 determination. 



This tooth is the second upper molar of the left side, and baa 

 been exhaustively compared with corresponding teeth by Dr. Roth, 

 who gives a good series of figures. It is readily distinguished from 

 the homologous molar in the genus Equus by the peculiar form of 

 its two inner columns — a fact which I have been able to verify by 

 the examination of an extensive series of specimens, both recent 

 and fossil, in the British Museum. Further comparison, indeed, 

 shows that it must be referred to the extinct Pampean genus 

 Onohippidium ~. Dr. Roth assigns it, apparently quite rightly, to 

 the same species as a maxilla from the Pampean formation of the 

 Province of Buenos Ayres, for which he proposes the name of 

 Onohippidium scddiasi. 



Large Extinct Rodent. 



The proximal end of the femur of a large rodent (no. 52) has 

 already been recognized by Roth, and compared with the extinct 

 Megamys. It cannot be more exactly determined. 



Existing Species. 



One imperfect fragment of pelvis and sacrum (no. 48) seems to 

 belong to a puma {Fells concolor) of rather large size ; but it is not 

 sufficient for precise determination. 



The small mandibular ramus of a musteline (no. 51 ) referred by 

 Dr. Roth to Mephitis suff'ocans does not pertain to this genus and 

 species. Mr. Oldfield Thomas determines it to belong to the rare 

 Lyncodon patagonicug, which still lives in Patagonia and has not 

 hitherto been found fossil. A slightly larger extinct species of 

 the same genus has been described by Ameghino on the evidence 

 of a skull from the Pampean formation near T,njan, in the 

 Province of Buenos Ayivs \ 



A cranium, some vertebra?, and a tibia and libula (nos. 53, 54) 

 appear to represent the existing Ctenomys magellanicus, as noted 

 by Roth. 



1 Dr. Moreno has lately received reports of bear-like tracks in remote parts 

 of the Cordillera, which he thinks may imply that a species of Arctotherium 

 still lives in Patagonia. 



2 F. P. Moreno, Revista Mus. La Plata, vol. ii. ( 1891). p. (15 ; R, Lydekker, 

 Vnales Mus. La Plata— Paleont. Argentina, vol. ii. pt. 3 1 1S'»3), p. 77, pi. xxix. 



8 F. Ameghino, op. cit. (188K). p. 324. 



