34 BIRDS OF THE HAWAIIAN GROUP. 



Order PASSERBS.-Perching Birds. 



Families. 



Tarsus compressed behind, forming a comparatively sharp edge, or else hind 

 claw longer than its digit and straight, the enveloping membrane {i. ^., tarsal sheath) 

 divided into not more than three longitudinal segments which may be either cut up 

 into transverse segments or fused into continuous plates. (Sub-order Osanes.) 



a. Posterior half of the tarsus not compressed but rounded and divided into dis- 

 tinct segments like the anterior half (Page 35.) Alau'didse. 



aa. Posterior half of the tarsus compressed with the lateral plates forming 

 a sharp ridge. 



b. No bastard primary {i. e., the first primary obsolete), the outer primary 

 falling short of the wing by less than the length of the hind toe without the claw; bill 

 of various forms but with a well developed operculum ; tongue a more or less modified 

 tubular brush. A very heterogeneous family embracing the greater part of the 



Hawaiian passerine avi-fauna (Page 39.) Drepan'ididse. 



bb. Tenth or outer primary present, but varying in length. 



C. Primaries apparently only nine, the tenth being exceedingly rudi- 

 mentary ; tip of the bill not hooked ; bill straight and cone-shaped. Bird sparrow-like. 

 d. Wing less than 2.40; nostrils placed high on the bill nearer the 



culmen than the tomium (Page 39.) Ploce'idae. 



dd. Wing more than 2.48; bill notched and with a few bristles 



at the gape ; true sparrows (Page 38.) Fringiiridse. 



CC. Primaries obviously ten, or else the bill hooked; tarsus longer 

 than the middle toe with claw. 



e. Tarsus more or less distindlly scutulate in front. 



f. Tail feathers normal, but not especially long; nasal 

 feathers erect or inclined backward ; nasal bristles either present or wanting. 



g. No nasal bristles; nasal feathers inclined back- 

 ward somewhat; first primary minute, not reaching to the tip of the wing coverts; 



white patch on the wing at base of primaries (Page 37.) Stur'nidae. 



gg. Nasal bristles present. 



h. Large birds ; wing more than 4.00. 



(Page 35.) Cor'vidae. 

 hh. Small birds ; wing less than 4.00. 



i. First primary not over .30; bill slender 



and notched near the tip; nasal openings not pronounced. . . . (Page 58.) Sylvi'idse. 



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