1915.] Allen, Review of the South American Sciuride. 209 
patch in winter pelage, obsolete or absent in summer pelage; upper surface 
of feet colored like rest of upperparts. 
Total length (2 adult males, collector’s measurements), 390, 380 mm.; 
head and body, 200, 200; tail vertebree, 190, 180; hind foot (in dry skin, 
with claws), 49, 48; ear, 23, 23. 
Skull, adult female (Prov. del Sara, Bolivia), occipito-nasal length, 48; 
zygomatic breadth, 28; interorbital breadth, 15.3; postorbital breadth, 17; 
breadth of braincase, 21; length of nasals, 14; diastema, 12; maxillary 
toothrow, 8. . 
Specemens examined, 7.— Bolivia: Santa Cruz de la Sierra, 2 “ cotypes”’ 
(Br. Mus.); Chulumani, La Paz, 1 (Br. Mus.); Central Bolivia, 1- (Br. 
Mus.); Santa Cruz de la Sierra, 1, topotype (Pittsb. Mus.); Province del 
Sara, 1 (Pittsb. Mus.); Rio Mapaiso, Rio Grande, 1 (Pittsb. Mus.). Five 
of the specimens were collected by T. Steinbach, the two cotypes by Bridges. 
On Steinbach’s label on the specimen from Rio Mapaiso is written: “The 
only specimen seen south of Santa Cruz.” 
Remarks.— Leptosciurus leucogaster is similar to L. ignitus but paler 
above throughout, with the belly white instead of deep yellow, and much 
larger in all external measurements. Gray’s specific name leucogaster 
(Macroxus leucogaster) is available in the present connection, as the species 
is not a Sciurus in a strict sense, and the name therefore not preoccupied 
by the earlier Scturus leucogaster of F. Cuvier. 
Genus Notosciurus Allen. 
Plate IX, Figs. 1-3; Text Figs. 4 (p. 162), 20, 21. 
Notosciurus ALLEN, Bull. Amer. Mus. Nat. Hist., XX XIII, p. 585, Oct. 8, 1914. 
Type, Notosciurus rhoadsi Allen. 
Size small, tail of medium length, the tail vertebrae 46% of total length; 
naked part of plantar surface of hind feet restricted to distal half, the rest 
heavily furred; posterior pad large and nearly square, occupying the whole 
breadth of the sole, close to the toe pads; number of mammee not known, 
but probably 6. 
Premolars ¢ (?).!. Skull in general form much like that of Guerlinguetus 
estuans, but the preorbital portion is relatively much shorter, and the 
brea’th at the anterior end of the zygomata much less, the zygomatic arches 
1 The single known skull is young, still retaining the milk premolar (p‘), so that it is 
impossible to say whether or not the permanent dentition might include p’. 
