a ra 
NO. 9 BIRDS OF ISLA COIBA, PANAMA—WETMORE 7 
Museum, was shipped from the field, probably on the collector’s 
arrival in Chiriqui, since Rothschild described the wood pigeon, and 
Hartert a hummingbird and the pepper-shrike of Coiba, in the Bulle- 
tin of the British Ornithologists’ Club for December 30, 1901. At 
the close of the Panamanian work sets of the skins were purchased 
by the American Museum of Natural History, where they were cata- 
loged in July 1902. The Chicago National History Museum also has 
a small lot of specimens from this collection, presented by Batty, and 
entered on the Museum records on January 4, 1906. The remainder 
came to the American Museum, apparently as a gift from the col- 
lector, where they were cataloged in March 1910, nearly four years 
after Batty’s accidental death in Chiapas, on May 26, 1906. A few 
of the skins have gone in exchange to other institutions, but with the 
accession of the Rothschild collection, the American Museum of 
Natural History now houses the greater part of this material. The 
Coiba material has been mentioned from time to time by Griscom, 
Hellmayr, and Zimmer in various studies, and Eugene Eisenmann 
in 1950 described the white-throated robin from the island as a 
distinct subspecies. 
In my work on Panamanian birds over a period of years I have 
examined Batty’s specimens from Coiba from time to time and have 
been puzzled occasionally by discrepancies apparent in dates and 
other details. These could not be explained until I began the identifi- 
cation of my own collection. As this work has progressed, it has 
become clearly evident that some of the field labels for Batty’s skins 
must have been made later, after the work was completed, and that 
there was a certain amount of mixing through which a number were 
marked with the wrong localities. This I have been able to determine 
because of the considerable differences that exist between various 
of the mainland birds and their representatives on Coiba. For ex- 
ample, in the series of the woodpecker Centurus rubricapillus, there 
are six specimens marked “Coiba” of which five are obviously the 
peculiar subspecies found on the island, and one as obviously repre- 
sents the mainland race. Among the skins of the wood pigeon 
Leptotila plumbeiceps battyi, restricted to Coiba, there is one imma- 
ture bird of the distinct species Leptotila v. verreauxi also labeled 
“Coiba,” an obvious error as only L. p. battyi occurs on the island. 
Similar mixing is evident in the crimson-backed tanager, where 20 
skins labeled “Coiba” in major part represent Ramphocelus dimidi- 
atus pallidirostris of Chiriqui, and only a few the Coiba subspecies. 
The pepper-shrike of Coiba, described by Hartert, is a very distinct 
form, with clearly marked characters. The Batty collection, in addi- 
