534 Mr. O. Thomas on Mammals 
Cavia Azarw of Wagner *) is also a large form closely allied 
to the true C. aperea, as is shown by some topotypical 
examples recently sent home by Mr. W. Foster. On the 
other hand, the well-known “ Quiso” of Argentina is a 
small form, but grey in colour, and appears to need a new 
name. Its description is given in the paper next following. 
20. Sylvilagus minensis, sp. n. 
Size decidedly greater than in the true Rio Janeiran 
S. brasiliensis. General colour above dark grizzled buffy, 
fairly uniform, heavily lined with black on the back, clearer 
on the sides. Under surface dull whitish, sometimes washed 
with pale buffy ; collar coarsely grizzled buffy, like the sides. 
Top of muzzle and centre of forehead rufous ; nape brighter 
and clearer rufous. Lower margins of nostrils prominently 
white. Supraorbital white (or, rather, cream-coloured) lines 
present, broad in front of and behind eyes, narrowed just over 
them by a darkened lateral projection of the forehead colour, 
which comes down nearly to the eyelid. Below the eye there 
is but little sign of the light marking. Behind, between 
eye and ear, the cheek is darkened, in some cases almost 
black. Outer side of ears grizzled like crown basally, dark 
brown terminally. Hairs of inner surface dull buffy. Fore- 
arms and hands rufous anteriorly, white internally ; hind 
limbs similar, but the feet marbled with white above. Tail 
rudimentary ; its hairs grey basally, buffy terminally. 
Skull comparatively slender, with a long and narrow 
muzzle. Interorbital region flat or slightly concave. Post- 
orbital processes long and broad, hollowed out and almost 
spoou-shaped above; not anchylosing with the brain-case in 
any of the specimens examined. Occipital shelf narrowing 
backwards, with convergent sides and rounded posterior 
angles. Enamel of upper incisors quite simple, following the 
outline of the teeth. 
Dimensions of the type, measured in the flesh :— 
Head and body 370 millim. ; hind foot, s. u. 75, ¢. u. 82; 
ear 4, 
Skull: greatest length 72, basilar length 55; zygomatic 
breadth 85°5; nasals 30 (diagonally) x 14:4; interorbital 
breadth 17; breadth of brain-case 27°3 ; palate length from 
henselion 29; diastema 22; palatal foramina 18 x 6:7. 
Type. Male. B.M. no. 1. 11.3.81. Original number 652. 
Collected 3rd May, 1901. 
* Schr. Saug. Suppl. iv. p. 65 (1844), 
