new Species of Oryzomys, Ge. 539 
Skull markedly smaller than in C. aperea, closely like that 
of the true C. rufescens. As compared with that of the other- 
wise very similar C. 7. guiane, the nasals are more evenly 
pointed behind and there is less tendency towards the forma- 
tion of postorbital processes. 
Dimensions of the type (measured in the flesh) :— 
Head and body 251 millim.; hind foot (s. u.) 40; ear 23. 
Skull: greatest length 62; basilar length 50; greatest 
breadth 35; nasals 22 x9; interorbital breadth 13°5; palate 
length 19; length of tooth-row (alveoli) 15 ; diastema 17:5 ; 
palatal foramina 7. 
Hab. (of type). Goya, Corrientes. Other specimens seen 
from La Plata and elsewhere in the Argentine Republic. 
Type. Female. B.M. no. 98.3. 6.2. Collected 15th July, 
1895, by Mr. R. Perrens. 
Sylvilagus paraguensis, sp. n. 
Closely allied to S. mznensis, but rather smaller. General 
colour above similar, but in the two specimens more mottled, 
though this is probably due to the preparation of the skins. 
Rufous of top of muzzle less extended on the crown. Supra- 
orbital light hairs almost obsolete, but the white below the 
nostrils well marked. Nuchal patch duller rufous. Ears and 
limbs as described in S. minensis. Under surface as in that 
species, but the dark collar broader, the belly rather whiter, 
and the groins more distinctly washed with buffy. Tail 
apparently rather more evident, blackish above, tipped with 
buity, yellowish buffy below. 
Skull as compared with that of S. mdnensis smaller, 
markedly shorter and stouter in the muzzle, which is also 
flatter above in the postnasal region. Postorbital processes 
more pointed, less concave above. Occipital shelf parallel- 
sided, not narrowing backwards. 
Dimensions of the type (measured in the flesh) :— 
Head and body 350 millim. ; hind foot, s. u. 70, c. u. 76 ; 
ear 5D. 
Skull: greatest length 67°3; basilar length 53 ; zygomatic 
breadth 34; nasals 26°5 (diagonally) x 14:1; interorbital 
breadth 16; breadth of brain-case 263 palate length from 
henselion 26°2 ; diastema 20°5; palatal foramina 16x 6. 
Hab. Sapucay, KE. of Asuncion, Paraguay. 
Type. Female. Original number 383. Collected 30th 
May, 1901, by Mr. W. Foster. ‘Iwo specimens. 
