148 Nelson Descriptions of New Squirrels from Mexico. 

 Sciuropterus volans goldmani subsp. nov. 



MEXICAN FLYING SQUIRREL. 



Type No. 132,833, adult male, U. S. National Museum, Biological Sur 

 vey Collection. From 20 miles southeast of Teopisca, Chiapas, Mexico, 

 collected April 8, 1904, by E. A. Goldman. Original No. 16,667. 



Geographic distribution. Highlands of Chiapas and Guatemala. 



Subspecific characters. Much like S. volans quercrli, but top of nose white ; 

 postocular are a much darker ; and underside of flying membrane deep 

 ochraceous buff. 



Description of type. Top of head and upper parts of body nearly uniform 

 reddish brown, slightly more reddish than in Sciuropterus volans querceti ; 

 upper surface of flying membrane blackish slate color ; top of tail cinnamon 

 brown ; tops of fore-feet dingy whitish ; tops of hind-feet dusky, toes dingy 

 whitish ; top and sides of nose, lower part of cheeks, and sides of neck to 

 back of ears whitish ; area between eye and ear dusky, shading down into 

 dingy grayish brown on cheeks and sides of head below ears ; supraloral 

 spot whitish; underside of neck and body white with a pale suffusion of 

 buff; underside of flying .membrane deep ochraceous buff; underside of 

 tail dingy buff. Ears large and broad. 



Measurements of type. Total length, 237; tail vertebrae, 1 12 ; hind foot, 30. 



Skull characters. Skull scarcely distinguishable from that of S. volans 

 querceti. 



Measurements of skull of type. Basalilar length of Hensel, 28 ; interorbital 

 width, 7.5; zygomatic width, 22 ; greatest width of b rain case, 17.5 ; length 

 of nasals, 10.2; width of rostrum, 6; depth of rostrum, 7. 



General notes. This flying squirrel is so closely related to S. volans that I 

 have felt constrained to consider it a subspecies although its range is com 

 pletely isolated by some hundreds of miles of intervening desert country 

 from its nearest relative to the north. The resemblance between the 

 Florida and Mexican flying squirrels is remarkably close ; the white top 

 to the nose, slightly more reddish upperparts, and rich fulvous on the 

 underside of the flying membrane are about the only characters that dis 

 tinguish the Chiapas animal. The lack of contrast between the top of the 

 head and back, the dark postocular area, and the white nose separate it 

 from Texas specimens. 



Sciurus poliopus senex subsp. nov. 



MICHOACAN SQUIRREL. 



Type No. 126,208, adult female, U. S. National Museum, Biological 

 Survey Collection. From La Salada, 40 miles south of Uruapan, southern 

 Michoacan, Mexico. Collected March 14, 1903, by E. W. Nelson and E. 

 A. Goldman. Original No. 16,127. 



Geographic distribution. Below 4,000 feet in the valley of the 'Balsas 

 River (and tributaries) in central and southern Michoacan and adjacent 

 parts of northwestern Guerrero. 



