266 Bulletin American Museum of Natural History. [Vol. XXXIV, 
Hadrosciurus flammifer (7homas). 
Text Fig. 9 (p. 163); Plate XII, Figs. 4-6; Plate XIV, Fig. 7, 8. 
Sciurus flammifer THomas, Ann. and Mag. Nat. Hist. (7), XIV, p. 38, July, 
1904.— ALLEN, Bull. Amer. Mus. Nat. Hist., XX, p. 340, Oct. 8, 1904 (La Union, 
Hi] Llagual, and Suapure, Venezuela); ibid., XXVIII, p. 146, May 27, 1910 (Rio 
Mocho, Venezuela); ibid., XXX, p. 254, Dec. 2, 1911 (El Llagual), 
Type locality.— La Union, Caura district, Middle Orinoco, Venezuela. 
Geographic distrubution.— Orinoco basin, from. at least Ciudad Bolivar 
to Suapure. 
Description.— Pelage long and coarse with very little underfur. Head 
and ears bright rufous, the ears with a postauricular patch of soft, light 
rufous hairs; rest of upperparts grizzled yellow and black, darkening on the 
lower back and rump to mixed rufous and black; lips and chin yellow 
orange; rest of underparts clear white, separated from the upperparts by an 
orange lateral line; outside of limbs bright rufous, inside white like the 
ventral surface; upper surface of feet orange rufous, lighter than the limbs; 
basal third of tail black narrowly fringed with orange red; rest of the tail 
(which is broad and bushy) orange on both surfaces. 
The above description is based on a topotype, which agrees in every 
particular with the type. Five other specimens from La Union (and hence 
topotypes) are melanistic. In four of them the pattern of coloration is the 
same as in the type, but the head, lower back and limbs are duller, darker 
rufous; the rest of the upperparts is a grizzle of pale yellow and black - the 
underparts are dusky brown with a rufescent tinge, but no two of them are 
quite alike; tail brownish black (quite black at base) with a slight wash of 
fulvous, the hairs annulated broadly with brownish black and fulvous, with 
fulvous tips. The remaining specimen is both albinistic and melanistic, 
the head and feet being mixed white and rufous, and the ventral surface 
white with scattered black hairs. Of four specimens from El Llagual three 
are melanistic and one is like the type, but no two of the melanistic 
specimens agree in color. A single specimen from Ciudad Bolivar is also 
melanistic, while six from Suapure are like the type of the species. Of the 17 
specimens in the American Museum collection 8 are normal and 9 are 
melanistic. 
Total length (type, ex Thomas, l.-c.), 598 mm.; head and body, 285; 
tail vertebrae, 313; hind foot (s. u.), ida ee 70. Ten specimens La 
Union and en total length, 580 (540-610): head and body, 274 
(254-289); tail vertebrae, 310 (280-320); hind foot (ec. u.), 66.5 (64-67). 
Skull (5 topotypes), total length, 65.5 (64-67); zygomatic breadth, 38 
