PEROGNATHUS. HETEROMYS. 255 



lobes high; tail lontjer than head and body, crested; soles naked; 

 skull long, narrow; mastoids small. 



Color. Above grizzled yellowish brown lined with black; lateral 

 stripe pale fulvous; beneath white. Tail above sooty black, beneath 

 white. 



Measurements. Total length, 195: tail vertebra?, loi; hind foot, 

 24; ear, 6.5. 



a.—dispar. {Ferognathi/s), Osgood, N. Am. Faun., No. 18, 1900, 

 p. 58. 



Type locality. Carpentaria, Santa Barbara County, California. 



Geogr. Distr. " Coast Valleys of California from San Bernar- 

 dino to San Benito County, and north along the foothills of the west 

 slope of the Sierras to Placer County." 



Genl. Char. Larger than /'. californiciis, and paler. 



Color. Above bister; lateral line pinkish or ochraceous buff; 

 under parts buffy white. Tail bicolor. 



Measurements. Total length, 218; tail vertebra, 120; hind 

 foot, 27. 



392. spinatus. {Perognathus), Merr., N. Am. Faun., No. i, 1889, 

 p. 21. 



Ty/<e locality. "Twenty-five miles below The Needles, Colorado 

 River, California." 



Gcogr. Distr. Desert region of southern California, south into 

 lower California. 



Genl. Char. Size medium; tail longer than head and body, 

 crested, tufted; antitragal lobe large; soles naked; rump spinous. 



Color. Above drab gray lined with black; lateral stripe wanting; 

 fore legs, feet and under parts white. Tail above dusky, below 

 white; pencil dusky. 



Measurements. Total length, 179; tail vertebrae, 104; pencil, 15; 

 hind foot, 21; ear from crown, 3.5. 



G5. Heteromys. 



I. iri; p. ^; M. t^, = 20. 



Heteromys. Desm., Mamm., 1822, p. 313. 



Molars rooted; flattened spines mingled with the fur. Skull 

 almost flat above, slightly arched in middle of superior outline, 

 nasals projecting beyond incisors; mastoids level with plane of occi- 

 put; zygomata depressed, but do not dip to level of palate; occiput 

 horizontal, flat; tail long, exceeding body and head; soles hairy with 

 five tubercles. 



