PEROGNATHUS. 251 



Measurements. Total length, 195; tail vertebra*, iii; hind foot, 

 26; ear, 6. 



A. Ohaetodipus. 

 " Mastoids moderately developed, not projecting behind plane 

 of occiput; interparietal broadly pentagonal, or strap-shaped; mas- 

 toid side of parietal not longest; audital bulla; separated anteriorly 

 by full width or nearly full width of basisphenoid." 



Fig. 57. PEROGNATHUS (CHAETODIPUS) FEMORALIS. 

 No. 5065 Field Columbian Museum Coll. Nat. size. 



Upper tooth row. 

 Enlarged 8 times. 



Lower tooth row. 

 Enlarged S times. 



383. baileyi. [Poognathits), Merr., Proc. Acad. Nat. Scien. Phil., 



1894, p. 262, fig. I. 



Type locality. Magdalena, Sonora, Mexico. 



Geogr. Disir. Seventy miles southwest of Tucson, Arizona, into 

 Sonora, Mexico and northern Lower California. 



Genl. Char. Large; tail very much longer than head and body; 

 mastoids considerably developed; bulla nearly meeting below basi- 

 sphenoid; interparietal pentagonal, broadest anteriorly. 



Color. Above drab brown lined with black; beneath white; pale 

 lateral stripe; tail above dusky; beneath white. 



Measurements. Total length, 210; tail vertebra, 122; hind 

 foot, 27. 



384. hispidus. {Perognatlii/s), Baird, Mamm. N. \m., 1857, p. 421. 

 /ascidtt/s, Baird, N. Am. Mamm., 1857, p. 420. 



hispidus, Baird, N. Am. Mamm., 1857, p. 421. 

 spilotiis, Merr., N. Am. Faun., No. i, 1889, p. 25. 

 Type locality. Charco Escondido, Mexico. 



Geogr. Distr. Southern and western Texas, north to Oklahoma, 

 south to Mexico. 



