THE BIRDS OF THE NATUNA ISLANDS 89 



Although the female is somewhat more huffy on the under surface 

 than is the male, this race does not seem to be different in color from 

 the other subspecies. 



3. Orthotomus sericeus eupolius, new subspecies. 

 Orthotomus ruficeps Axjct. (part), nee Lesson. 



Subspecific characters. — Similar to Orthotomus sericeus sericeus, but 

 bill larger; wing, tail, and tarsus somewhat longer; gray of upper- 

 parts paler and less brownish (more purely gray). 



Description.— Tji>e, adult male, U.S.N. M. No. 200605, Sibutu 

 Island, Philippine Islands, January 7, 1906; Dr. E. A. Mearns. 

 Original number, 13861. Pileum, lores, periophthalmic region, and 

 post-ocular region, between burnt sienna and chestnut; cervix, upper 

 half of sides of neck, back, scapulars, and rump, rather deep and 

 somewhat brownish neutral gray; upper tail coverts between olive- 

 brown and army brown ; tail rather light auburn ; wings between hair 

 brown and chaetura drab, the outer margins of the quills dark drab, 

 the inner margins, except terminal portion of primaries, wood brown; 

 exposed surface of superior wing quills, gray like the back; lower half 

 of sides of head and of neck, together with lower surface, white, a 

 little washed with gray on sides, also washed slightly on sides, and 

 more so on abdomen, with cream color; tliighs between Sanford's 

 brown and auburn; lining of wing white except for a broad spot of 

 auburn on outer posterior portion. 



Measurements. — Six males: Wing, 51.5-57 (average, 53.4) mm.; 

 tail, 43-46.5 (44.8); exposed culmen, 15-17 (16.1); height of bill at 

 base, 3-4 (3.5); tarsus, 22-22.5 (22.3); middle toe without claw, 

 11-12 (11.3). 



Seven females: Wing, 44-53 (average, 50.1) mm.; tail, 33.5-45.5 

 (40.5); exposed culmen, 14-16 (15.1); height of bill at base, 3-4 

 (3.5); tarsus, 19-23 (21.4); middle toe without claw, 10-11.5 (10.8). 



Geographic distribution. — Southwestern Philippine Islands. 



4. Orthotomus sericeus hesperius, new subspecies. 

 Orthotomus ruficeps Auct. (part), nee Lesson. 



Subspecific characters. — Similar to Orthotomus sericeus sericeus ^ 

 from Borneo, but smaller; and upper parts (except pileum) somewhat 

 darker, more brownish (less clearly grayish). 



Description. — Type, adult male, U.S.N.M. No. 170785, Linga 

 Island, Rhio Archipelago, July 19, 1899; Dr. W. L. Abbott. Pileum, 

 lores, orbital region, and supra-auricular area, reddish brown, between 

 auburn and burnt sienna; back, scapulars, and rump, deep mouse 

 gray with a wash of brownish, the cervix more rufescent, forming 

 the transition to the pileum; upper tail coverts dull drab; tail 



