Account of Observed Forms of Larynx. 27 



In the Ampelinae, as in the Piprinae, the peculiar cartilages of the memhrana tym- 

 paniformU, which are characteristic of the Tyranninae, are wanting. The Eurylaiminae of 

 the Old World are close to the Amjielinae—that is, Eurylainms and Calyptomena. I have 

 examined Eurylaimus coiydon Temm., the type of the genus Corydon Less. In this bird 

 I remarked no muscular fibres on the larynx. 



(iv.) Organ of Voice of the Tyranninae and Fluvicolinae. 



The Muscicajndae of the New World, or Tyrannidae, are separated from those of the Old 

 World, not only by the want of the highly muscular larynx, but also by external characters ; 

 their feet are covered on the hinder, or inner, side with a band of small scales, or are quite 

 naked, while the Muscicapidae of the Old World possess the bilaminate tarsus of Sino-ino- 

 Birds. Further, the Tyrannidae have a well developed first primary, which is completely 

 aborted in the Muscicapidae of the Old World, as Swainson has already shown. In short, 

 they are perfectly distinct families. Gray has united them in his family of the Mvncicapidae 

 (as Cuvier in Muscicapa), and in it has separated the Tyranninae, Muscicapinae , and others ; 

 but his Muscicapinae, as with Swainson, is a collection of South American Passerines 

 without the muscular organ of voice, together with Muscicapidae of the Old World with 

 this organ, and contains birds of three dififerent families. 



In the family of the Tyrannidae, the genera of the Tyranninae and Fluvicolinae ofier some 

 interesting variations from the general ground- type of larynx without complex vocal 

 muscles. The only feature common to all the genera is the possession of a single muscle, 

 which may be very broad and thick, as in most of the Tyranninae and Fluvicolinae, but in 

 some it is so small, that it only appears to be a prolongation of the lateral muscle of the 

 trachea. All have a cartilago arytaenoidea in the memhrana tympaniformis, and, in most, 

 some of the upper rings of the bronchi are perfect, so that they resemble the trachea. Some 

 genera ofier very remarkable peculiarities. One of the chief forms of those with a single 

 thick muscle was observed by Audubon. 



SanrojiJiagus Sw., Tyrannus Cuv., Tyrannula Sw., Elaenia Suud., Plafyr/iyncJius Desm., 

 and in general the Tyranninae have a thick broad laryngeal muscle, which is not attached to 

 the posterior face of the larynx. 



In Saurophagus sulphuratus Sw. {Tyrannus sulphiratus Cuv.), the first five bronchial rino« 

 are broad and touch ; the first four are not at all moveable, and indeed the first three partly 

 blend on their outer sides. The first three bronchial rings are perfect. The muscle 

 is inserted into the fourth, and into the hinder part of the fifth bronchial rino" (half-rino-). 



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