1915.| Allen, Review of the South American Sciuride. ae 
and measured by Captain Wirt Robinson, U. S. A.), 395.6 (883-412 mm.); 
head and body, 205 (195-216); tail vertebrae, 193.5 (182-199); hind foot 
(c. u.), 51.4 (50-53). : 7 
Skulls of the same specimens, total length, 50.4 (50-51.7); zygomatic 
breadth, 29 (28-30); interorbital breadth, 15.9 (15-16.2); breadth of brain- 
case, 22.4 (22-23°; length of nasals, 15.6 (15-16.5); diastema, 12.1 (12- 
12.5); maxillary toothrow, 8.5 (8.2-8.8). 
Specimens examined, 39.— Venezuela: 1, type, by designation of 
Thomas, Dyson coll., without definite locality (Br. Mus.); San Julian, 1, 
San Esteban, 2 (Br. Mus.); San Julian, 20 (Robinson coll., Nat. Mus.); 
San Julidén, 2 (Robinson coll., Mus. Comp. Zoél.); without definite locality, 
1 (Nat. Mus.); San Julian, 1, Macuto, 1, mountains near Maracay, 2 (Field 
Mus.); San Julian, 2, Guiguas, 3, and San Esteban, 3 (Am. Mus.). 
Remarks.— As shown by the above-cited references, Mesoscvurus griseo- 
gena griseogena has had a checkered nomenclatorial history. When first de- 
scribed by Gray it was assigned a range extending from Mexico through 
Central America to Venezuela and Bogota, and was formerly considered 
referable by Allen, Alston, and Thomas (1877-1880) to Guerlinguetus estu- 
ans, either as a synonym or as a variety, all the small tropical American 
squirrels, whether red-bellied or white-bellied, then being considered as 
merely forms of estuans. In 1901 Thomas, when describing his Sciurus 
griseogena meridensis, designated “ Venezuela” as the type locality, and 
indicated on the label one of Dyson’s specimens as the type, Dyson’s speci- 
mens (cited by Gray) best agreeing with Gray’s description. The exact 
locality of Dyson’s specimen has not, to my knowledge, been indicated, but 
some of the birds he collected in Venezuela have been recorded by Sclater * 
as having been collected at Coriana, near Cariaco, Cariaco, Galipan (alti- 
tude 8000 ft.), and Cuman4, and hence in the Cumana Mountains, to the 
eastward of the Cordillera de la Silla. 
In 1900 Captain (now Colonel) Wirt Robinson, U. 5. A., collected 27 
specimens of this squirrel at San Julian, on the northern coast of Venezuela, 
a few miles east of La Guaira, near sea level. All the specimens were taken 
between July 13 and August 10, and 17 of the 27 specimens have been exam- 
ined by me in the present connection. In order authoritatively to deter- 
mine the species a specimen was sent by Robinson and Lyon to Mr. Oldfield 
Thomas of the British Museum for comparison with Gray’s type of his 
Macroxus griseogena. Thomas reported: “The squirrel is very typical of 
S. griseogena Gray, the specimen, No. 102721, being more exactly like the 
type than any others of the large numbers we have here” (Robinson and 
1Proc. Zool. Soc. London, 1855, pp. 88, 237, 251, 259, and elsewhere. 
