446 Mr. O. Thomas on 
Caviella australis nigriana, subsp. n. 
Size slightly larger than in australis. Colour less oliva- 
ceous, more drabby. 
Skull with tapering muzzle, as in australis ; premaxille 
similarly pushed forwards, so as to be seen clear in front of 
the nasals, but the incisors themselves comparatively ortho- 
dont (index in type 95°). Bulle very large in extreme cases, 
and always somewhat larger than in australis, the length 
ranging from 14°2 to 15:4 mm. 
Type-skull: occipito-nasal length 46°2 mm. ; occipito- 
incisive length 47°8 ; nasals, length 15, breadth anteriorly 5:4, 
posteriorly 7:5; interorbital breadth 9°8; bullee, oblique 
leneth 15:4, 
Range. Basin of the Rio Negro, extending on the west 
into that of the Upper Chubut. Type from Neuquen, 
R. Negro; other specimens from Nahuel Huapi, Leleque, 
Upper Rio Chubut, Pileatieu, Upper Rio Negro, Carmen de 
Patagones, and “ Mouth of Rio Negro” (Darwin). 
Type. Adult female. B.M. no. 11.11.19.3. Collected 
November 1910 by E. Weiske. Presented by the Hon. N.C. 
Rothschild. Nine specimens examined. 
Caviella australis joannia, subsp. n. 
Paler and more distinctly drab than in nigriana, the back 
rather paler and more yellowish than “ light drab.” 
Muzzle less strongly tapering than in négriana, though 
more so than in menas. Premaxille not pushed forwards, 
the incisors not or scarcely visible from above in front of the 
nasals. Interorbital space rather broad. Palatal foramina 
longer, narrower, less strongly triangular than in the more 
southern forms. Middle of posterior edge of palate commonly 
projecting or flattened, not forming a definite angle. Baullee 
fairly large, though smaller than in the largest examples 
found in nigriana, 14°4-14°6 mm. in length. 
Type-skull: occipito-nasal length 49°3 ; occipito-incisive 
Jength 49°8; nasals, length 18°5, breadth anteriorly 6:1, 
posteriorly 7*1;. interorbital breadth 12°2; length of bulla 14°6. 
Range. Southern San Juan and Mendoza. ‘Type from 
Cafiada Honda, San Juan. Alt. 500 m. 
Type. Adult female. B.M. no. 21.4. 8.5. Original 
number 1246. Collected 12th December, 1920, by E. Budin. 
Presented by Oldfield Thomas. Ten specimens. 
In spite of the considerable distance between San Juan 
and Neuquen, this race is very similar to C. a. niyriuna, but 
is distinguishable by the characters above given. 
