TROCHILHLE. CLXII. 271 



uniform purplish, its feathers narrow; 9 without red, the tail 

 variegated; no scales on crown. L. 3^. W. 1$. T. 1^. B. f. 

 E. N. Am. ; abundant in summer, hovering about flowers. (S. Am. 

 name, Colibri.) 



ORDER XL VI. PASSERES. (THE PASSERINE BIRDS.) 



Toes always 4 ; feet fitted for perching ; the hind toe always on 

 the level of the rest, its claw at least as long as that of the mid- 

 dle toe ; joints of toes 2, 3, 4, 5, respectively, from first to fourth ; 

 none of the toes versatile, and none webbed ; wing coverts few, 

 chiefly in two series; tail feathers 12; primaries 10, but in most 

 of the families the first one is reduced in size, and often rudimen- 

 tary and displaced ; musical apparatus more or less developed ; 

 sternum of a uniform passerine pattern; palate aBgithognathous. 

 Nature altricial. 



This order includes about 6000 known species, or more than half 

 of all the kinds of birds. They represent the " highest grade of 

 development and the most complex organization of the class ; their 

 high physical irritability is co-ordinate with the rapidity of their 

 respiration and circulation ; they consume the most oxygen and 

 live the fastest of all birds." (Cowes.) 



A considerable number of anatomical characters (for which see 

 Stejneger, " Standard Natural History," p. 458, et seq.), are more 

 or less perfectly distinctive of the Passeres. These cannot, how- 

 ever, be discussed here. The group is divided, on anatomical charac- 

 ters, into about 5 suborders. Two of these groups, the Clamatores 

 and the Oscines, are represented in our fauna. The latter, charac- 

 terized especially by the perfect musical apparatus, comprises the 

 vast majority of the Passeres. (Lat., passer, sparrow.) 



Families of Passeres. 



a. Tarsus with its hinder edge rounded ; encircled by a single horny envelope 

 divided into scutella anteriorly and on outer side, this sometimes ex- 

 tending all round (though separated by a seam along inner side), but 

 often widely separated on inner side or behind or both, the intervening 

 space occupied by granular scales, reticulations, or plain naked skin; 

 musical apparatus imperfect; primaries 10, the first about as long as 

 second. (Clamatores.} 



b. Inner toe free at base from middle toe; tarsus not reticulate behind; 

 bill hooked at tip, with long rictal bristles. . . . TYRANNID^E, 163. 

 aa. Tarsus with its hinder edge compressed, forming a sharp, nearly undi- 

 vided ridge (except in the Larks, which may be known by the long, 

 nearly straight hind claw); musical apparatus highly developed; pri- 

 maries properly ten, but the first short, or spurious, or sometimes rudi- 

 mentary and misplaced, so that but nine are evident, in which case the 

 first developed primary is about as long as second. ( Osdnes.) 



