354 PEROGNATHUS. 
Fic. XLIX. PEROGNATHUS MERRIAMI. 
MERRIAM’S PocKET MOUSE. 
MERRIAM’s Pocket Mouse. 
Type locality. Brownsville, Cameron County, Texas. 
Geogr. Distr. Alta Mira, State of Tamaulipas, Mexico, into 
Texas and New Mexico. 
Genl. Char. Size of P. flavus, color more yellow, sides golden. 
Color. Autumn Pelage. Above yellow, heavily lined with black; 
sides golden, sparsely mixed with black; beneath white; thighs 
golden; feet white; tail pale brownish yellow above, becoming 
blackish at tip; beneath paler. 
Summer Pelage. Above ochraceous, lined with black; lateral 
stripe ochraceous; under parts white; ears dusky; aural spot buff; 
tail pale grayish brown, lightest beneath. This phase of pelage repre- 
sents P. mearnst Allen. 
Measurements. Total length, 118; tail vertebre, 55; hind foot, 
16; ear, 4. Skull: basilar length of Hensel, 14.8; occipito-nasal 
length, 20.4; greatest mastoid breadth, 11.2; length of interparietal, 
2.3; greatest width of interparietal, 3.6. 
360. flavus (Perognathus), Baird, Proc. Acad. Nat. Scien. Phil., 
1855, p. 332. Elliot, Syn. N. Am. Mamm., 1901, p. 244. 
Bairp’s Pocket Mouse. 
Type locality. El Paso, El Paso County, Texas. 
Geogr. Distr. State of Chihuahua, Mexico, into southeastern 
Arizona and Texas. 
Genl. Char. Size very small; ear without antitragal lobe; tail 
less than head and body; audital bulla meeting below basisphen- 
oids. 
Color. Above pale fulvous, lined with black, no lateral stripe; 
feet and under parts white; buff patch behind ear, and white one 
on lower margin; orbital ring pale fulvous; tail pale brownish or 
olive gray, of nearly the same hue above and below. 
