Mammals from British Guiana. 149 
Dimensions of the type (measured in the flesh) :— 
Head and body 133 millim. ; tail 140; hind foot, s. u. 25, 
c.u. 26; ear 16. 
Skull: greatest length 32; basilar length 25°5; greatest 
breadth 16°6; nasals 10°8x 3:4; interorbital breadth 4°5; 
interparietal 4 x 10; palate from henselion 12°9; diastema 8 ; 
palatal foramina 6°8 x 2°5 ; length of upper molar series 4°4. 
Tyne. Male. B.M.no. 1.6. 4.81. From Kwaimattat, 
Kanuku Mts. Collected October 12. 
Although so closely similar to 2. venezwelw in colour and 
all essential characters, this species may be readily distin- 
guished by its much smaller size, as shown by the above 
dimensions. With the other two Guianan species, &. Maccon- 
nelli, de Wint., and &. Selateri, Thos., it has no near 
relationship. 
19. Holochilus guiane, sp. n. 
a-d. Four ad. and imm. skins. November 28, 1900. 
a. No. 179 the type. 
A middle-sized species allied to H. scdureus, from whose 
locality it is separated by the range of the Amazonian 
Hi. nanus. 
General colour of head and body grizzled greyish fawn, 
profusely mixed with blackish along the dorsal area. Sides 
gradually clearing and verging towards buffy cinnamon along 
the flanks ; in some of the younger specimens this part 1s 
almost ochraceous buff. Belly not sharply defined, the 
longer hairs cinnamon or buffy, the woolly hairs slaty basally, 
dull white terminally ; chin and inguinal regions entirely 
whitish, owing to the absence of the longer hairs. ars 
short, blackish externally, buffy internally. Arms and legs 
like body ; hands and feet glossy buffy white on the meta- 
podials, clearer white on the digits. The feet themselves 
appear to be longer in proportion to the size of the skull than 
in H. sciureus. ‘Tail shorter than head and body, finely 
scaly, thinly clothed with fine brownish hairs, the scales 
showing through; uniformly brown above, rather paler 
below. 
Skull as compared with that of Bahian specimens assigned to 
H, sciureus lighter and more delicately built throughout, less 
heavily ridged, with a narrower muzzle and more slender 
zygomata. Interorbital region flat, its edges square, not 
produced into heavy upstanding ridges as in AZ. scvureus. 
Front of anterior zygoma-root with a marked projection 
above, below which the edge is concave forwards. Palatine 
