446 ^"EW MAMMALS FROM MEXICAN BORDER— MEARNS. vol. xviii. 



from Fairbank, ou the Sau Pedro Elver, Arizona. Externally it is dis- 

 tinguislied from that species by its paler coloration, slightly smaller ears, 

 and stouter body. The largest skulls of P. arizonw equal the average 

 size of F. torniUo, but the shape differs considerably therefrom. In 

 both, the rostral portion is long and high, this character sufticing to 

 distinguish these species from sonoriensis and the other subspecies of 

 Peromyscus texamis. The skull of P. tornillo is low and squarish, its 

 zygomatic arches standing strongly out in front, as sharp elbows at 

 right angles to the cranial axis. 



PEROMYSCUS TEXANUS MEDIUS, new subspecies.' 

 SAN DIEGO PLAINS-MOUSE. 



Between the ranges of the subspecies gamhelii and thurheri, both 

 dark-colored races of Peromyscns teaanns, there is a narrow strip of 

 southern and Lower California, bordering the Pacific Ocean for several 

 hundred miles and extending east to the Coast Range of mountains, 

 occupied by the present race, which differs from either of those above 

 mentioned in beiug paler, with more drab and clay-colored tints. It is 

 smaller than P. /. gamhelii, with much larger ears, and a shorter tail. 

 Its paler, more ochraceous coloration at once distinguishes it from P. t. 

 ihurheri, with which it agrees in size. From P. /. deserticola, of the 

 interior deserts, it differs in being less robust, and in having somewhat 

 larger ears, and much darker colors. 



Ty2)c. — Ko. 01050, U.S.X.M. (Coll. International Boundary Commis- 

 sion). Adult male from Nachoguero Valley, Lower California. Collected 

 by Dr. Mearns, June 4, 1894. Original number, .3023. 



Description of type. — Above wood brown, shading to russet on cheeks 

 and sides, thickly mixed with black, giving a dusky dorsal area; ears 

 clove brown, densely clothed, with faint hoary edging; top of head 

 wood brown, paler than back; feet and under parts pure M'hite; tail 

 black above, white on sides and l^elow. Length, 100 mm.; tail verte- 

 bra?, 70; ear from crown, 17; hind foot, 21. 



PEROMYSCUS TEXANUS CLEMENTIS, new subspecies. 

 SAN CLEMENTE MOUSE. 



Foruis of Feromyscus texanus have been collected on the Coronados 

 Islands, and on Santa Eosa, Santa Catalina, and San Clemente, of the 

 Santa Barbara group. Of these I have only examined those from 



'For the species of mouse to Avbich this subspecies aud the uext belong, the earliest 

 name available is Hesperomiis texanus, Woodhouse. Two of Dr. Woodhouse's speci- 

 mens are still in the U. S. National Museum. One of these, the type, is alcoholic, 

 aud the other a skiu. From these I have removed the skulls for examination. 

 Baird's Hcsperomys texanus is composite, four siiecies of Peromyscus and an Onychomys 

 Laving been included in his " list of specimens," as proven by specimens still extant. 

 I have seen no evidence of intergradatiou between P. leucopus aud the forms of P. 

 texanus. 



