28 Golchwtn — Twelve Neiv Wood Rats. 



Crnninl cliaracifrs. — Skull large and massive, rather smoothly rounded, 

 well arched across anterior roots of zygomata; rostrum short and heavy; 

 nasals wedge-shaped, reaching posteriorly to plane of orbits ; braincase 

 somewliat truncate posteriorly ; interparietal large and rectangular with- 

 out trace of a posterior angle; spheiio-palatine vacuities completely closed 

 by palatines; vomer prolonged posteriorly as a thin vertical plate along 

 median line of presphenoid, partiallj'^ dividing posterior nares, and ending 

 in a point at suture between presplienoid and basisphenoid ; bulUe small 

 and heavy, somewhat pear-shaped, and pointed anteriorly. 



Measurements. — Type: Length (head and body), 187; tail vertebrae (in- 

 complete), 60; hind foot, 37. 



Neotoma martinensis sp. nov. 



Type from San Martin Island, Lower California, Mexico. Adult female. 

 No. 81,074, U. S. National Museum, Biological Survey Collection. July 17, 

 1896. A. W. Anthony. Original number 39. 



General cJiaracters. — Size medium; tail moderately long, tiiinly cov- 

 ered with short hairs ; outer sides of hind legs conspicuously blackish. In 

 color closely resembling N. anthonyi, but tail more scantily haired, and 

 cranial characters very different. 



Color. — Upperparts grayish brown, evenly mixed dorsally with dusky 

 hairs, becoming lighter and somewhat suffused with pale buff' along 

 sides ; underpai-ts creamy white, the fur everywhere deep plumbeous 

 basally ; ears dusky ; upi)er sides of forearms dusky brown ; outer sides of 

 hind legs and inner sidesof ankles conspicuously blackish ; feet, including 

 the sides of the soles to point well above heels on hind feet, pure white; 

 tail bicolor, brownish black above, grayish below. 



Cranial characters. — Skull of medium size, rather smoothly rounded, 

 high and well arched acioss anterior roots of zygoniiita ; tempoi'al ridges 

 faintly developed and widely separated ; nasals very long, abruptly narrow- 

 ing posteriorly, and reaching well beyond plane of lachrymals; frontal 

 region narrowly constricted anteriorly, broadening posteriorly, the upper 

 surface nearly flat and witliout well developed lateral ridges; bulUe rather 

 small and somewhat pear-shaped, the meatus very large and widely open. 



Measurements. — Type: Total length, 342; tail vertebrae, 167; liind foot 

 (dry skin), 35.7. 



Neotoma nudicauda sp. nov. 



Ti^pe from Carmen Island, Lower California, Mexico. Nearly adult 

 female. No. 79,073, U. S. National Museum, Biological Survey Collection. 

 October 14, 1895. J. E. McLellan. Original number 1517. 



General characters. — Size medium ; ears large ; tail moderately long, 

 nearly naked. Similar in general to N. arenacea, but color paler and 

 cranial characters different. 



