Order LAGOMORPHA. HARES, RABBITS, 

 and PIKAS 



Resembling the Rodentia but upper incisors four in num- 

 ber ; a large functional pair with enamel extending to posterior 

 face of tooth (as contrasted to enamel restricted to anterior 

 face of tooth in the Rodentia), and a small pair without cutting 

 edges directly behind them; upper and lower jaws opposing 

 each other only one side at a time and motion of mastication 

 lateral in consequence; bony palate very narrow from front 

 to back; tail short to very short; habit terrestrial. 



Family Ochotonidae. Pikas 



Size small; ears broad and rounded, small as compared to 

 the Leporidse; no visible, external tail; legs rather short and 

 hind legs not much longer than forelegs; feet digitigrade; toes 

 five in front, four behind; upper incisors deeply grooved in 

 front. 



Genus Ochotona. ^ Pikas or Conies 

 Dentition: Incisors, f ; Canines, §; Premolars, |; Molars, §=26 



Pika. — Ochotona princeps 



and related forms 



Names. — Rocky Mountain Pika; Rocky Mountain Cony; 

 Rocky Mountain Rock-rabbit; Little Chief Hare. Plate 

 XXXVI. 



General Description — Body robust; tail so short as to be 

 practically non-existant ; legs short and hind legs but little 

 longer than forelegs; five toes on forefeet, four on hind 

 feet, a naked pad at base of each toe, palms and soles densely 



^ For a full and up-to-date revision of this genus see A. H. Howell, 

 North American Fauna, No. 47, 1924. 



470 



