TYRANNID^l. — CLXIII. 273 



o. Birds of large size; (wing more than 4) Corvid^e, 1G5. 



oo. Birds of small size; (wing less than 4). 



p. Bill not notched Parid^e, 177. 



pp. Bill notched toward the tip, very slender. . . . Sylyiid.e, 178. 

 iin. Nasal feathers erect or directed backward, not covering nostrils; bill 

 rather slender, the culmen convex; first primary not very short. 



Trogi.odytid^e, 175. 

 jj. Tarsus booted, without distinct scutella except near the base; rictal bristles 

 present. 



q. Birds of small size; (wing less than 3); young unspotted. 



Sylviid.e, 178. 

 qq. Birds of moderate size (wing more than 3); young spotted. 



Turdid.e, 179. 



Family CLXIII. TYRANNID^. (The Flycatchers.) 



Primaries 10 ; the first more than f length of second, longer than 

 in any other of our passerine birds; bill typically broad, triangular, 

 depressed, abruptly hooked and notched at tip, with long rictal 

 bristles ; commissure nearly straight ; nostrils small, usually partly 

 concealed. Tarsus with its back and sides as well as the front 

 covered with scutella, so that there is no undivided ridge behind, 

 as in must other Passer es. Feet small. Mouth capacious; vocal 

 apparatus mesomyodian, i. e. the " syrinx with fewer than 4 dis- 

 tinct pairs of intrinsic muscles inserted at the middle of the upper 

 bronchial half rings, constituting an uncomplicated and ineffective 

 musical apparatus." (Coues.) Changes of plumage slight; ours 

 mostly olivaceous. 



A large family of 80 genera, and more than 300 species; all 

 American and mostly tropical. All are insectivorous, most of 

 them pre-eminently so ; they are, therefore, in our latitude, 

 migratory. 



a. Bill of typical form, depressed, hooked at tip, with strong rictal bristles. 

 b. Outer primaries, one or more of them, attenuate ; crown in adult with a 

 concealed red or yellow crest, 

 c. Tail deeply forked, much longer than wings. . . . Milvulus, 452. 



cc. Tail not forked, not longer than win^s Tyrannus, 453. 



66. Outer primaries not attenuate; crown without concealed bright-colored 

 crest. 



d. [Wings and tail with chestnut; length 8 or more]; head slightly 

 crested ; wings little longer than tail. . . . Myiarchus, 454. 

 dd. [Wings and tail without chestnut; general color olivaceous; length 

 less than 8.] 

 e. Wings at least 6 times as long as tarsus; (W. 3 to 4^). 



Contopus, 456. 

 ee. Wings not more than 5 times as long as tarsus, little longer than 

 tail. 

 /. Bill rather narrow (black in our species; wing more than 3J). 



Sayornis, 455. 

 ff. Bill broad (usually pale below in our species ; wing less than 3 £). 



Empidonax, 457. 



18 



