INTRODUCTION 3 



intended primarily for the identification of specimens in hand. The 

 arrangement in the keys is artificial, and may not follow any order 

 of close relationship. The order of the families is that in my latest 

 revision of the classification for living and fossil birds of the world 

 (Smithsonian Misc. Coll., vol. 139, no. 11, June 23, 1960, pp. 1-37). 



References to literature, given in parentheses, are sufficiently com- 

 plete to allow their consultation if desired. A complete bibliography, 

 and with it a gazetteer of localities, will be included in the final part. 



The account of each bird begins with the scientific name, followed 

 by vernacular names in English and in Spanish. Where the species is 

 divided into geographic races, if two or more of these are found in 

 Panama, general information that applies to all is given under a 

 species heading. This includes brief phrases on characters that may 

 help in identification, and a description. The subspecies follow, each 

 with its scientific name and reference, details of color, size, or form 

 on which the race has been recognized, measurements, range in the 

 Republic, and any other pertinent information. If the nominate 

 form is included among these, reference to this name is given under 

 the subspecies in question. Where this race does not reach Panama, 

 the species heading carries this reference. In variable species of wide 

 range, where only one of the forms is found all these data are in- 

 cluded under the heading with the trinomial scientific name. Ver- 

 nacular names used apply to the species as a whole. No such names 

 are given to separate subspecies. 



Vernacular names have been selected with care, with particular 

 reference to usage in standard works that cover the area. This fre- 

 quently has involved choice, since in wide-ranging species divided 

 in several geographic races it was early custom to assign such a 

 name to each subspecies, often without regard to its related forms. 

 Modern practice gives vernacular names to the species in its entirety, 

 since the former method was cumbersome and frequently mislead- 

 ing. In the case of migrants from the north, the names used are 

 those of the official A.O.U. check-list (Check-list of North American 

 Birds Prepared by a Committee of the American Ornithologists' 

 Union, fifth edition, 1957). With others, particularly tropical species 

 of wide distribution, names frequently have varied so that a choice 

 has been necessary. The attempt with these has been to select the 

 term most often used, and the one most appropriate. In this, the list 

 proposed by Eugene Eisenmann (The Species of Middle American 

 Birds, Trans. Linn. Soc. New York, vol. 7, 1955) is definitely 

 valuable. 



