PASSERES. 321 



Order PASSERES. — Perching Birds. (Page 3.) 



Families. 



a 1 . Tarsus cylindrical, or with hinder portion rounded; encircled with a single 

 horny envelope (divided into scutellse anteriorly and on outer side), this 

 sometimes extending 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. (Suborder Clamatores.') 

 b 1 . Inner toe with basal phalanx united to that of middle toe ; posterior face of 



tarsus retioulate Cotingidae. (Page 323.) 



b 3 . Inner toe entirely free at base from middle toe ; posterior face of tarsus not 



reticulate Tyrannidse. (Page 326.) 



a 2 . Tarsus compressed behind, with comparatively sharp posterior edge (or else 

 hind-claw longer than its digit, and straight), the enveloping membrane 

 divided into two or three longitudinal segments, which may be either divided 

 into transverse segments, or scutellse, or fused into continuous plates. (Sub- 

 order Oscines.) 

 ¥. Posterior half of tarsus not compressed, but rounded, and divided into dis- 

 tinct segments, or scutellse, like the anterior half. 



Alaudidse. (Page 346.) 

 b*. Posterior half of tarsus compressed, with two lateral plates uniting behind 

 in a comparatively sharp ridge, and for the most part undivided. 

 c 1 . Primaries apparently only 9 (the 10th being exceedingly rudimentary), 

 the tip of the bill not hooked. 

 d 1 . Bill variously formed, but gape never twice as long as culmen; 

 outer primary never twice as long as innermost. 

 e 1 . Bill straight. 



f l . Bill conoid ; if slender, the angle of the gonys forward of 

 the nostril. 

 g 1 . Bill without notch, and without bristles at gape. 



Icteridae. (Page 365.) 

 g 3 . Bill notched, and with bristles at gape. 



h 1 . Nostrils concealed by feathers, or pointed an- 

 teriorly and overhung by a distinct scale 

 or horny membrane, or else base of cutting- 

 edges forming a distinct angle. 



Fringillidae. (Page 382.) 



h 3 . Nostril exposed, rounded anteriorly, without 



distinct overhanging scale or membrane, and 



cutting-edges of bill not forming a distinct 



angle at the base.. Tanagridse. (Page 453.) 



41 



