TTEANNIDiE, FLYCATCnERS. 



167 



Obs. Several additional species of jays have been ascribed to our countrj^, but 

 apparently npon insuflicient evidence or erroneous information. 



Suborder CLAMATOBES. Non-melodious Passeres. 



As already intimated (p. 70), the essential character of this gi'oup, as distin- 

 guished from Oscmes, is an anatomical one, consisting in the non-development of a 

 singing apparatus ; the vocal muscles of the lower larynx (syrinx) being small and 

 weak, or else forming simply a large fleshy mass, not separated into particular 

 muscles. This character, however, appears subject to some uncertainty of deter- 

 mination, and probably does not always correspond with the only external character 

 assignable to the group, namely, a certain condition of the tarsal envelope rarely if 

 ever seen in the higher Passeres. If the leg of a kingbird, for example, be closely 

 examined, it will be seen covered with a row of scutella forming cylindrical plates 

 continuously enveloping the tarsus like a segmented scroll, and showing on its 

 postero-internal face a deep groove where the edges of the envelope come together ; 

 this groove widening into a naked space above, partially filled in behind with a 

 row of small plates. With some minor modifications, this condition marks the 

 clamatorial birds, and is something tangibly different from the ordinary oscine 

 character of the tarsus, which consists in the presence on the sides of entire 

 corneous laminae meeting behind in a sharp ridge ; and even when, as in the 

 case of EremoiMla and Ampelis, there is extensive subdivision of the laminaj 

 on the sides or behind, the arrangement does not exactlj' answer to the above 

 description. The Claniatores represent the lowest Passeres, approaching the large 

 order Picarice (see Ijeyond) in the steps by which they recede from Oscines, yet well 

 separated from the Picarian birds. The families composing the suborder, as 

 commonl}' received, are few in number ; only one of them is represented in North 

 America, north of Mexico. 



Family TYRANNID.^. Flycatchers. 



While having a close general resemblance to some of the foregoing insectivorous 

 Passeres, the North American representatives of this family will be instantly distin- 

 guished by the above-described condition of the tarsus ; and from the birds of 

 the following order by the Passerine characters of twelve rectrices, greater wing 

 coverts not more than half as long as the secondaries, and hind claw not smaller 

 than the middle claw. 



This family is peculiar to America ; it is one of the most extensive and character- 

 istic groups of its grade in the New World, the Tanagridce and Trocldlidcti alone 

 approaching it in these respects. There are over four hundred current species, 

 distributed among about a hundred genera and subgenera. As well as I can 

 judge at present, at least two-thirds of the species are valid, or very strongly 

 marked geographical races, the remainder being about equally divided between 

 slight varieties and mere synonyms. Only a small fragment of the family is repre- 

 sented within our limits, giving but a vague idea of the numerous and singularly 

 diversified forms abounding in tropical America. Some of these grade so closely 

 toward other families, that a strict definition of the Tyrannidoe, becomes extremely 

 difficult ; and I am not prepared to oflTer a satisfactory diagnosis of the whole group. 

 Our species, however, are closely related to each other, and may readily be defined 

 in a manner answering the requirements of the present volume. With a possible 

 exception, not necessary to insist upon in this connection, they belong to the 



