206 Bulletin American Museum of N atural History. [Vol. XXXIV, 
having been published in the same paper, and the former will be first con- 
sidered. | 
Some twenty years ago (hence before cuscinus was described), I identified 
a single specimen of squirrel from Yungas, Bolivia, as zgnitus Gray, and a 
restudy of this specimen, in connection with considerable ‘“ cuscinus”’ 
material, leads me to believe that this determination was correct. The 
type locality of zgnitus was within the present known range of ochrescens, 
and not the Sta. Cruz de la Sierra region, where the well-known collector 
Steinbach has found Gray’s Macroxus leucogaster but no squirrels of the 
cuscnus group. This being the case, and there being nothing contra- 
indicative in the description, Macroxus ignitus is apparently the earliest 
name for any member of the cuscinus group. 
Macroxus irroratus as clearly belongs also to the cuscinus group. This 
was recognized by Thomas when, in 1897, he described cuscinus, but owing 
to certain slight discrepancies between the description of zrroratus and his 
type of cuscinus, he decided to hold the name irroratus in abeyance. In view 
of the now known wide range of individual variation in undoubted cuscinus 
specimens, the supposed importance of these discrepancies practically dis- 
appears. | , 
Both egnitus and irroratus are very unlike any other squirrels, although 
both have been referred to “@stuans,” as estuans was formerly understood. 
They are nearest in size and tooth structure to Gray’s Macrozus leucogaster, 
but the original descriptions forbid their reference to this species. No other 
small squirrel (except species of Microsciurus) is known to occur nearer than 
900 miles of the range of the ignitus-irroratus (“cuscinus”) group, namely 
the Ecuador forms of hoffmanni of the genus Mesosciurus. Its range is 
thus widely separated from that of any other with which it has any near 
alliance. 
Leptosciurus ignitus irroratus (Gray). 
Text Fig. 3 (p. 162); Plate VII, Figs. 10-12; Plate XIII, Figs. 7, 8. 
Sciurus estuans Tscuuni (not of Linné), Fauna Peruana, I, Therologie, 1844~ 
46, p. 158, part. | 
Macroxus trroratus Gray, Ann. and Mag. Nat. Hist. (8), XX, p. 431, Dec. 1867 
(Upper Ucayali River, Peru). 
Sciurus estuans cuscinus THomas, Ann. and Mag. Nat. Hist. (7), III, p. 40, Jan. 
1899 (Ocabamba, Peru); ibid., VII, p. 187, Feb. 1901 (Rio Inambari).— ALLEN, 
Bull. Amer. Mus. Nat. Hist., XIII, p. 226, Nov. 16, 1900; ibid., XIV, p. 46, Jan. 31, 
1901 (Inca Mines, near Juliaca, Peru). 
Lype locality.— Upper Rio Ucayali, Peru. 
Geographic distribution.— Andes of southeastern Peru. 
