242 ^^EJ^ north American mamma ls— tr ve. vol. xvu. 



SCAPANUS DILATUS, new npecies. 



Exterior uukiiowii. 



Dental formula. — I. f , C. j, PM. f, M. |. Penultimate premolar with 

 a posterior cusi). 



Size of skull moderate. Maxillary above the first molar broad (equal 

 iu breadth to the interparietal bone), with a strong ridge sei)arated from 

 the root of the zygoma by an emargiuation. Antero-external angles 

 of the interparietal not rounded oft". Angular process of the mandible 

 narrow, strongly uncinate. 



Dimensions of sl-ull (tyj^e). — Greatest length, 34 mm.; basilar length 

 (Hensel), 28.5 mm.; greatest breadth across maxillte, 10.5: greatest 

 zygomatic breadth, 14 mm.; length of tooth-row, 15 mm.; length of 

 parietals, 11.1 mm.; breadth of interparietal, 10.5 mm. 



Ti/pe.—^o 1286, Merriam Collection, Fort Klamath, Oreg. (Skele- 

 ton.) Collected by Capt. C. E. Beudire. 



Paras c a l o p s , new genus. 



Premolars, |. Molars with a trilobed internal basal projection 

 extending across the bases of both externals cusps. Tympanic bullje 

 incomplete and annular. Pelvis with no osseous bridges opposite or 

 posterior to the acetabulum, connecting the sacral vertebme Avith the 

 pelvis. Extremity of the spinous processes of the sacral vertebrae 

 connected by a continuous band of bone, but the intervals between the 

 spines themselves not filled in with bone. 



Tail hairy. General color black. 



Type. — Scalops brewer i. Bach man. ' 



MYODES XIGRIPES, new si)ecies. 



Upper surfaces nearly uuiform cinnamon-gray, without bands or 

 spots. Sides, including the lower part of the cheeks and neck, clear 

 tawny brown. Under surfaces paler tawny, which tint is gradually 

 merged into the stronger color of the sides. Nose black. Fore feet 

 black above, tawny below. Hind feet black both above and below. 

 Tail bicolored, black above, pale tawny below. 



Dimensions (from dry skin; type), — Head and body, 130 mm.: tail 

 vertebra?, 13 mm.; hind foot (without claw), 17.5 mm. 



Type.— No. 59152, U. S. N. M., male, St. George's Island, Alaska. 

 Collected by Charles H. Townsend, August 18. 



M T o T o M Y s , new genus. 



General appearance that of Synaptomys. Ears moderate. Tail 

 short, hairy. Thumb with a strap-shaped nail, as in Myodes. Mammae, 

 4 pairs. 



Skull similar to that of Synaptomys. Incisors obliquely beveled and 

 broadly grooved on the bevel. Molars rootless. Upper molars as in 



