1914.] 



REITHKODONTOMYS FULVESCENS GKOUP. 



49 



distinct median band; ears dull sepia, clothed on inner surface with 

 tawny hairs; underparts grayish white, often with a distinct tinge of 

 pale buff. Immature pelage: Decidedly more grayish, often lacking 

 entirely the bright tawny shades. Variation: There is considerable 

 variation in color in this subspecies, even among adult specimens. 

 This consists both in the intensity of the ochraceous shades and in the 

 amount of blackish suffusion on the back and sides. Some individ- 

 uals have the whole back heavily sprinkled with blackish hairs, 

 while others show only a rather narrow band down the median line. 

 A specimen from Matagorda Island (March 31) is quite exceptional 

 in being intensely tawny over the entire upperparts with only faint 

 indications of black hairs on the back, thus closely resembling speci- 

 mens of Peromyscus nuttalli. Other individuals from the same island 

 are normal in color. 



SkuU. — ^Very similar to that of intermedins, but braincase averag- 

 ing a little broader. 



Measurements. — Adult from Houma, La.: Total length, 176; tail 

 vertebrse, 100; hind foot, 20. Average of 5 adults from Velasco, 

 Tex. : 170; 97; 21. Average of 9 young adults from Sour Lake, Tex. : 

 162 (154-170); 89 (83-94); 20 (19-21). Skull: (See table, p. 81). 



Remarlcs. — This subspecies is a well-marked race, occupying the 

 humid or Austroriparian division of the Lower Austral Zone, west of the 

 Mississippi Eiver. Although it shows considerable individual varia- 

 tion and occasional specimens — chiefly immatm^e ones — are hardly 

 distinguishable from specimens of intermedins, the general intensity 

 of coloration shown by any series of specimens makes identification 

 possible at a glance. The type and topotypes of " cJirysotis^^ have 

 been examined and found to agree perfectly with specimens of auran- 

 tius from eastern Texas. 



Specimens examined. — Total number, 88, from the following local- 

 ities : 



Louisiana: Avery, 5; Belcher, 1; Foster (5 miles east of Shreveport) 1; Houma, 

 1; Iowa Station, 1; Lafayette, 2; Lecompte, 1 (skull); Mer Rouge, 4; Natchi- 

 toches, 1. 



Arkansas: Beebe, 2; Delight, 4. 



Missouri: Carthage, 2. 



Oklahoma: Dougherty, 3;^ Stilwell, 3. 



Texas: Barnard Creek, west of Columbia, 6; East Caranchua Creek, Matagorda 

 County, 2; Elliott, Matagorda County, 1; Hempstead, 8; Joaquin, 7; Mata- 

 gorda, 5; Matagorda Island, 5; Nacogdoches, 2; Selkirk Island, Matagorda 

 County, 1; Sour Lake, 10; Texarkana, 1; Velasco, 9. 



1 Collection Field Mus. Nat. Hist. 



28657°— 14 4 



