6 Review of the Genera zvhose Larynx has been already examined. 



The numerical relation of the so-called false Passerines to the Singing Birds appears 

 I'rom his investigations to be pretty much the same in North America as in Europe 

 and the Old World. Alcedo, Cj/pselns, and Caprimulgus ^ belong to both worlds ; instead of 

 Vimpa, Meroj)S, Coracias, and Em-T/stomus, there appear in the New World Trochilus, 

 Tyrannus, T^rannula, and Setopliaga ; the great majority of Passerines, Iwth in the 

 Old World and in North America, belong to the true Singing Birds. 



Prince Max von Neuwied, Eyton, v. Tschudi, and myself have described several of 

 the South American Passerines with reference to their organs of voice. 



Prince Max gave a figure ^ of the external appearance of the lower larynx of CJiasmo- 

 rhjnchus niuUcollis, from which it can be seen that the organ of this bird is very muscular, 

 but it leaves it doubtful whether the organ belongs to the so-called muscular organ 

 of voice. 



Blyth finds the muscular organ of voice in the Coting'ulae and Manakins^; he says 

 that he has opened several broad-billed Ti/rannidae and that they all possess the characters 

 of Singing Birds*; and that Thjtotoma is in all structui-al peculiarities a Singing Bird'. 

 But it is certain that neither the Cotingidae, Manakins, or Tyranmdae possess the muscular 

 organ of voice ; all the genera of these birds which I have examined wanting it. 



Eyton makes in the Appendix to Darwin's Zoology of the Voyage of H.M.S. Beagle, 

 part iiij Birds, London 1841-4, some anatomical remarks on Serpophaga alhocoronata, 

 Furnarius cunicularius, Upiicerthia dimetoria, Opeiiorliynclms vnlgaris, 0. antarcticns, 

 0. patagonicus, Pteroptoclios Tamil, P. albicolUs, Sj/vallaxis maluroides, PJiytofoma rara, 



and TrocMlw gigas. 



* . . . 



A. Wagner expresses in his Jaliresbericht "^ his regret that Eyton bad only directed 



his attention to the Sterno-tracheal muscles, and not to the proper muscles of the 

 lower larynx also ; and really, his information on the organ of voice of genera, 

 then examined for the first time, is very meagre and vinsatisfactory. It is said of 

 Serpopliaga that the trachea is supplied with the same muscles as in Songsters. Of 

 Phytoloma he says, Trachea with one pair of Sterno-tracheal muscles ; and further on 

 we learn nothing more than that the skeleton as well as the soft parts resemble those 

 of the genus Lo.r'ia. Eydoux and Souleyet" have quite overlooked the larynx in their 



' Tlie North-American forms of Cypselus (Acanihylis Boie), Caprimulgus (Antrostomus Gould), and 

 Chordmles (Sw.) were examined by Audubon. 



^ Beitrage zur Naturgeschichte von Brasilien, B. III. fig. i. 



' Mag. Nat. Hist. Vol. II. p. 264. ■* Ibid. p. 360. ^ Ibid. p. 600. 



' Erichson's Archiv, 1841, II. p. 64. 



' Voyage autour du monde sur la corvette la Bonite. Paris. Zoologie, T. I. p. 92. 



