92 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 134 
orange in males, that flash as they dart out or drop through the 
branches after flying insects, is attractive, and is the basis for the 
name in Spanish. Females collected January 19 and 21 have the 
lighter color that marks the typical race. Two adult males were 
secured January 13 and 15. 
BASILEUTERUS DELATTRII Bonaparte: Chestnut-capped Warbler, 
Reinita Cabecicastafia 
Basileuterus delattrii BONAPARTE, Compt. Rend. Acad. Sci. Paris, vol. 38, 1854, 
p. 383. ( Nicaragua.) 
These warblers are inhabitants of undergrowth, where they feed in 
low branches, or occasionally on the ground. On Coiba I encountered 
them from near the shoreline back through high forest in the in- 
terior of the island. They also came into thickets in abandoned 
fields near the work camps. They were common, but of secretive 
habit, keeping behind cover. As they frequently carry the tail at 
an angle over the back they often suggest wrens as they move about 
behind the screening twigs and leaves. At this season they were 
silent except for an occasional chipping call. Usually they are found 
in pairs, and during January most of those that I killed for specimens 
were nearly ready to breed. The Coiba population is so different 
from that of the mainland that it requires the following name: 
BASILEUTERUS DELATTRII ACTUOSUS subsp. nov. 
Characters.—Similar to Basileuterus delattru. mesochrysus Sclater,?° 
but bill larger, and coloration darker; back duller green; gray of 
hindneck slightly darker; under surface duller yellow; sides and 
flanks darker green. 
Description—Type, U.S.N.M. No. 461248, male, Isla Coiba, 
Panama, collected Jan. 23, 1956, by A. Wetmore (orig. No. 20409) : 
Forehead black, with the feathers tipped lightly with deep neutral 
gray ; crown dark russet ; hindneck between deep and dark olive-gray ; 
back and scapulars Roman green; lower rump, upper tail coverts and 
wing coverts serpentine green; remiges and primary coverts between 
deep and dark mouse gray, edged with serpentine green; rectrices 
deep mouse gray, edged with light serpentine green; lores black; a 
broad superciliary, extending to the nape, white; chin and malar re- 
gion, extending back beneath eye, white ; feathers on edge of eyelids, 
and a line extending posteriorly to above the ear coverts, black; ear 
26 Basileuterus mesochrysus P. L. Selater, Proc. Zool. Soc. London, vol. 28, 
1860, p. 251. (Bogota, Colombia.) 
