244 Bulletin American Museum of Natural History. (Vol. XXXIV, 
Total length (average of 20 specimens, collector's measurements), 
448 (413-457); head and body, 232 (220-246); tail vertebrae, 220 (205- 
236); hind foot, 61 (59-64). 
Skull (7 specimens), total length, 57 (55-59); zygomatic breadth, 33.6 
(33-34.5); interorbital breadth, 18 (17-19); breadth of braincase, 24.4 (23- 
95); length of nasals, 17.6 (17-18.3) ; maxillary toothrow, 9.2 (9-9.6). 
Specimens examined, 26— Panama: Lion Hill, 3 topotypes (Mus. 
Comp. Zodl.); Gatun, 14 (11 Nat. Mus., 3 Am. Mus.); Rio Indio, near 
Gatun, 6; Tabernilla, 2; Porto Bello, 1 (all in Nat. Mus.). 
Remarks.— This is the extreme phase of the gerrardi group as regards 
coloration, the usual median black dorsal band being merely incipient or 
obsolete, and the coloration of the upper parts pale ochraceous, finely lined 
with black. It is also the most western, occupying the lowlands of the 
central and western parts of Panama. To the eastward in Panama it 
grades into M. gerrardi choco (Goldman). The limit of its range to the 
westward has not been determined, but it apparently does not reach Chiriqui, 
where it is replaced by M. hoffmanni chiriquensis. 
Mesosciurus gerrardi choco (Goldman). 
Sciurus variabilis choco GOLDMAN, Smiths. Misc. Coll., LX, No. 22, p. 4, Feb. 28, 
1913. 
Type locality — Cana (altitude 3500 feet), eastern Panama. 
Geographic distribution Eastern Panama, “from sea level in the Tyra 
Valley to over 5000 feet altitude on the summits of the Pirri Range.’’— Gold- 
man, ?.°C. : 
Description.— Similar in coloration to Mesosciurus gerrardt morulus but 
general coloration slightly more refescent, and with a well developed dorsal 
band of black, barely indicated in morulus. Also similar in size and cranial | 
characters. 
Total length (average of 10 specimens, collector’s measurements), 446 
(430-465); head and body, 235 (220-249); tail vertebrae, 212 (207-223); 
hind foot, 61.3 (58-62). | 
Seven skulls, total length, 56 (54.5-58); zygomatic breadth, 33.3 (32- 
35); interorbital breadth, 18.5 (17.5-20); breadth of braincase, 24.4 (23- 
25.6); length of nasals, 18 (17-19); maxillary toothrow, 9 (9-9). 
Specimens examined, 28.— Panama: Cana, 5, type and 4 paratypes; 
Mt. Pirri, 6; Cerro Azul, 3; Marracante (sea level), 2; Boca de Cupe, 1 
(all Nat. Mus.). Colombia: Chepigana, 4; El Real, 7 (Amer. Mus.). 
Remarks.— As already noted, this subspecies intergrades to the west- 
