404 



PROCEEDINGS OF THE ACADEMY OF 



[1893. 



DESCRIPTIONS OF NEW SPECIES OF NORTH AMERICAN MAMMALS 

 WITH REMARKS ON SPECIES OF THE GENUS PEROGNATHUS. 



By SAMUEL N. RHOADS. 



The pocket mouse from Texas here described as new was obtained 

 during the past year by Prof. E. D. Cope and placed in the collec- 

 tion of the Academy of Natural Sciences of Philadelphia. 



The specimens of Perognathus lordi on which I have based the 

 duplicate description of that species, so imperfectly characterized by 

 Gray, were taken during a collecting trip in Washington and 

 British Columbia last year, and are included in the author's private 

 collection at the Academy. 



By the rediscovery of P. lordi of Gray I am enabled to throw 

 some light on certain questions of synonymy propounded by Dr. 

 Merriam in his monographic revision of the genus. 1 



The figure of skull of P. femoralis here given completes the 



illustrations of known species of the genus. 



1. Perognathus copei, sp. nov. (type No. 1612, ad. $ , Col. Acad. Nat. Sri., 

 Phila,, Staked Plains near Mobeetie, Texas, August 26th, 1893; col. by Prof. 

 E. D. Cope). 



Description. — Size small, somewhat greater than Baird's measure- 

 ments of P. flavus. Colors similar to Baird's description of P. mon- 

 ticola but smaller. Ears destroyed. Tail thickly covered with 



coarse hairs, concealing the annuli ; grayish 

 white above, pure white below, with terminal 

 pencil, slightly crested- penicillate. 



Beneath, including whisker patch and feet, 

 white. Upper back and head grizzled blackish 

 fawn, the black tips coarsely predominating. 

 Rump and thighs strongly washed with cinna- 

 mon, this color forming a broad posterior band 

 diminishing laterally to a faint line at fore- 

 legs; soles nearly naked, heel clothed with 

 bristly hairs halfway to toes, as in flavus; skull 

 similar to flavus but longer and narrower, the 

 mastoids less pronounced both laterally and 

 posteriorly, the interparietal a squarish pen- 



1 X. Amer. Fauna, No. 1, 1889. 



2 All figures twice natural size. 



