NO. 9 BIRDS OF ISLA COIBA, PANAMA—WETMORE 69 
from San José and Pedro Gonzalez Islands in the Perlas group, the 
comparative material available from the mainland and from Colombia 
was so meager that my identification of skins from the island locali- 
ties as arenarum was purely tentative. In the interim a fair series 
has been assembled through my own work in Panama and through the 
collections made by M. A. Carriker, Jr., across northern Colombia, 
so that now it is possible to deal with these birds with some certainty. 
In brief, the 19 skins from Panama now at hand are quite uni- 
formly gray on the dorsal surface, clear, light gray on the chest and 
foreneck, and paler yellow on the sides, with the axillars somewhat 
more yellow, being similar in these colors to typical S. a. arenarum 
from southwestern Costa Rica. The six obtained from Coiba Island 
agree with arenarum, as do also two from Taboguilla Island. The 
mainland series, which is uniform, includes skins from the eastern 
side of the Azuero Peninsula (Paris, Parita, Monagrillo, Los 
Santos), Canal Zone (Farfan, Corozal) and the eastern half of the 
Province of Panama (Chico, Chepo, Majé). 
The race S. a. atrirostris (Lawrence), with type locality Cartagena, 
northern Bolivar, Colombia, compared with arenarum, has the dorsal 
surface darker, slightly olive-gray, the crown cap slightly darker, and 
the sides darker, more grayish yellow. The fresh material now at 
hand in the National Museum collections includes a pair of topotypes 
from Cartagena, and a series of 12 others from Bolivar and northern 
Magdalena. The Io adults that I took on San José and Pedro Gon- 
zalez Islands, Archipiélago de las Perlas, in 1944 agree with atriros- 
tris and are so identified. They would seem therefore to represent 
an ancient establishment of the species, perhaps from the time when 
the formicariid Formicivora grisea, common across northern Colom- 
bia but found nowhere on the mainland of Panama, also reached the 
same islands. 
CAMPTOSTOMA OBSOLETUM (Temminck): Southern Beardless Flycatcher, 
Mofiona Lampiifia 
Muscicapa obsoleta TEmMiINnckK, Nouveau recueil de planches coloriées d’oiseaux, 
livr. 46, 1824, pl. 275, fig. 1. (Curytiba, Parana, Brasil.) 
The mojfiona lampifia is so small that it is probably more common 
on Coiba than is indicated by the four specimens obtained. One of 
these was secured in high virgin forest, the others in or near the 
mangroves along the beaches. Apparently they range across the high 
forest crown, as well as in the lower growth. They move rather 
quietly among the leaves, and when they fly usually disappear behind 
