Mr. O. Thomas on Neotropical Mammals. 243 
Dimensions of the type, measured in the flesh :— 
~ Head and body 127 millim.; tail 57; hind foot, s. u. 23, 
€.u. 25+ ear 15. 
Skull: greatest length 30; basilar length 24:4; zygo- 
matic breadth 17; nasals 11:1; interorbital breadth 4°7; 
breadth of brain-case 14 ; palate length 12°8; diastema 7°8; 
palatal foramina 7; length of upper molar series 5:3. 
Hab. Valle del Lago Blanco, Cordillera region of Southern 
Chubut Territory, Patagonia. 
Type. Male. Original number I. Collected 28th Sep- 
tember, 1900, by Mr. J. Koslowsky. ‘Ten specimens ex- 
amined. 
This species is the southern representative of A. macronyz, 
Thos., to which it is no doubt very nearly allied; but the 
fresh series now available indicates that it should have a 
name of its own. 
In company with the series of A. vestitus there are two 
examples of the other long-clawed southern group Notiomys, 
distinguishable by its very small and comparatively brachyo- 
dont molars from the more or less hypsodont Akodon, but I 
cannot definitely determine their species. From the descrip- 
tions given it seems not impossible that both ‘‘ Hesperomys 
(Acodon) Michaelsent,’ Matschie, and ‘‘ Oxymycterus micro- 
tis,’ Allen, belong to Noécomys, as their long claws, short 
tails, and very small molars agree precisely with what is 
found in that group. 
Ctenomys Azare, Thos. 
Ctenomys Azare, Thos. Ann. & Mag. N. H. (7) xi. p. 228 (1903). 
The locality of this animal proves unfortunately to have 
been wrongly given in the above description. 
The specimens were presented to the British Museum by 
Sefior Maximo Hopff, of Buenos Ayres, who handed them 
to the British Consulate there for transmission home. It 
happened, however, that a collection of Mr. W. Foster’s was 
coming home by the same intermediary, and Mr. Hopff’s 
specimens, which were not labelled, got placed with the 
latter and were considered to be part of it. 
Now, however, enquiry shows that the specimens were 
obtained in the Province of Buenos Ayres, on the central 
pampas, lat. 37° 45’ S., long. 65° W., 780 kilometres south- 
west of the capital, a region from which no examples of 
Ctenomys had previously been recorded. 
16* 
