NO. 9 BIRDS OF ISLA COIBA, PANAMA—-WETMORE 81 
foreneck and breast gray (instead of white as in bilineata) ; sides 
darker gray ; bill averaging broader. 
Description—Type U.S.N.M. No. 461129, male, Isla Coiba, 
Panama, collected Feb. 1, 1956, by A. Wetmore (orig. No. 20558) : 
Pileum, hindneck, and upper parts of sides of neck black, with a tiny 
white feather or two behind the nostril; back, scapulars, rump, and 
wing coverts somewhat darker than slate-gray ; tips of the gray upper 
tail coverts faintly white; primaries and secondaries dusky neutral 
gray, with outer webs edged with slate-gray, except for the two 
outer primaries; tertials edged broadly with white on outer webs, 
the edging becoming pale neutral gray toward the tip; tail black 
centrally, the two outermost rectrices white, except for the base, the 
next ones tipped broadly, and the fourth narrowly, with white; lores 
and a broad superciliary white ; eye ring black on lower eyelid, white 
on upper; a conspicuous black line extending from the eye to the 
back of the nape; rest of side of head, throat, ventral area of sides 
of neck, abdomen, and under tail coverts white; lower foreneck, 
breast, and sides pale neutral gray; edge of wing white, mixed with 
dusky neutral gray ; under wing coverts, and inner webs of primaries 
and secondaries, toward the base, white. Maxilla and tip of mandible 
dusky neutral gray; base of mandible neutral gray, becoming pallid 
neutral gray from the anterior part of the gonys back along the lower 
margins of the rami; tarsus and toes black (from dried skin). 
Measurements.—Males (9 specimens), wing 46.2-49.7 (48.5), tail 
41.8-46.3 (44.1), culmen from base 13.0-14.9 (14.0), tarsus 16.6- 
17.8 (17.2) mm. Females (6 specimens), wing 45.1-47.4 (46.6), 
tail 41.9-45.3 (44.0), culmen from base 13.8-14.8 (14.4), tarsus 16.2- 
17.5 (17.0) mm. 
Type, male, wing 49.7, tail 44.9, culmen from base 14.7, tarsus 
16.9 mm. 
Range.—Isla Coiba, off the Pacific Coast of Veraguas, Panama. 
Remarks.—Females, like the males, differ from the same sex of 
bilineata in darker color above. Below, the distinction is less striking, 
but still is evident. 
In citing these birds as races of Polioptila plumbea I have followed 
current usage, though not entirely satisfied that this is the proper 
treatment. The birds of this section of the genus are in need of 
detailed study. 
The subspecific name of the race described above is from the Latin 
cinericius, ash colored. 
