New Investigations into the Distribution of the Vocal Muscles. 1 1 



in Lanius Cuv., and Certhia Cuv. The Mitscicapidae of the Old World, Muscicapa in the 

 narrowest sense, both the European, Asiatic^ and African forms, as well as the African 

 Muscij}c(a Sw., and Flatystera Jard. Selb. possess the complex muscular organ of voice 

 of Singing- Birds. The American 3hiscicapidae, or Tyrannidae, have no muscular organ 

 of voice, but only one muscle, which may be thick, as in Tyrannus, Saurophagus, Tyrammla, 

 and Elaenia, or very thin as in Myiobius, Arundinicola, Pyrocej)halus, Todirostnim, and others. 



The genus CuUcivora Sw. [Sylvia bivittata Mus. Berol.), which is provided with a 

 muscular organ of voice, would make an exception, and would be the sole representative 

 of the Muscicaj)a of the Old World, in North America, and America generally, if this 

 genus belongs to the Muscicapinae, with which Gray places it. But CuUcivora appears 

 to have been more correctly placed by Swainson with the Sylvianae in consequence of the 

 presence of this organ. 



The Fluvicolinae have only a single vocal muscle. The Piprinae also have not 

 the complex muscular organ of voice, but a single vocal muscle, sometimes thicker, 

 sometimes thinner. 



The following is a list of all the genera of American Passerines without the complex 

 muscular organ of voice, which I have examined. 



Ckasmarhynchus Temm. 



Cotinga Briss. 



Gymnocephalus Geoffr. 



Mupicola Briss. 



Phibalura Vieill. 

 Pipra L. 

 Jodopleura Less. 

 Calyptura Sw. 

 Psaris Cuv. 

 Pachyrhamphus Gray. 

 Tyrannus Cuv. 

 Saurophagus Sw. 

 Machefornis Gray. 

 Tyrannula Sw. 

 Platyrhynchus Desm. 

 Elaenia Sund. 

 Myiobius Gray. 

 Arundinicola Cab. 



Pyrocephalus Gould. 



Fluvicola Sw. 



Centrites Cab. {Alauda rufa aul.) 



Colopterus Cab., n.g. 



Orc/nlim Cab. [Todus megacepkalus Sw.) 



Todirostrum Less. 



Todus L. 



Tkamnojihilus Vieill. 



Myiolhera 111. 



Conopophaga Vieill. 



Ckamaeza Vig. 



Tinactor Pr. Max. 

 Furnarius Vieill. 



Cinclodes Gray. 

 Synallaxis Vieill. 

 Xenops Hoffm. 

 Anabates Temm. 

 Bendrocolaptes Herm. 



C 2 



