THE cor. INS OR BOC-WHITES. I43 



Adult Male. — Differs chiefly from the male of O. pectoralis 

 in having the black band round the base of the throat narrow, 

 not extending over the chest, wliich is dull rufous-chestnut 

 like the rest of the under-parts. Total length, 7-8 inches; 

 wing, 4-5; tail, 2*5; tarsus, 1*2; middle toe and claw, 1-4. 



Adult Female. — Like the female of O. pedoralis, but slightly 

 larger. 



Range. — State of Jalisco, West Mexico. 



V. RIDGWAY'S COLIN. ORTYX RIDGWAYI. 



Colimis ridgwayi, Brewster, Auk, ii. p. 199 (1885); Bendire, 



N. Amer. B. p. 10 (1892). 

 Ortyx ridgivayi, Ogilvie-Grant, Cat. B. Brit. Mus. xxii. p. 422 



(1893). 

 Adult Male.— Distinguished from all the preceding species by 

 having the eyebrow-stripes, chi/i, a?id t/woat black ; and from 

 the two following species by having the chest and under-parts 

 pale reddish brick-colour. Total length, 8 '4 inches; wing, 

 4-5 ; tail, 2-5 ; tarsus, \'2 ; middle toe and claw, 1-35. 



Adult Female. — Closely resembles the females of O. pectoralis 

 and 0. graysoni. Measurements as in the male. 



Range. — Arizona, United States of North America, and 

 Sonora in Northern Mexico. 



Habits. — Mr. Herbert Brown, who was the first to obtain 

 examples of this species, gives the following note : — "The habits 

 of the Masked Bob-White, so far as we know them, appear to 

 resemble very closely those of the Common Quail {O. vir- 

 ginianus), only slightly modified by the conditions of their 

 environment. They utter the characteristic call of 'Bob- 

 White' with bold, full notes, and perch on rocks or bushes 

 while calling. They do not appear to be mountain-birds, 

 but live on the mesas (table-lands) in the valleys ^nd pos- 

 sibly in the foot-hills. 



