180 



NORTH AMKiaCAN BIRDS. 



Ictenis bullnrki. 



diversity ami lirilliiuicv of pluinage as tlio others are (with few exceptions) 

 for their uniform sombre black, scarcely reheved by other colors. Of the 

 four genera of this subfamily, recognized by Gray, all but Caciciis are well 

 represented in tiie United States. This differe from all the rest in hav- 

 ing the culmeu widened and much depressed towards the btise, where 

 it advances in a crescent on the forehead, separating the frontal plumes. 

 In tlie otlier genera the culmon ad\ances somewhat on the forehead, but 

 it is in a narrow acute point, and not dilated. 



In studying the North Ameri- 

 can Orioles we ha\e found it 

 e.xceedingly difficult to arrange 

 them in any sharply defined 

 sections, as whatever characters 

 be taken as the basis of classi- 

 fication, the other features will 

 not correspond. Thus, species 

 with the bill of the same pro- 

 portions and amount of curva- 

 ture differ in the shape and 

 graduation of the tail, while tails of the same form are accompanied by 

 entirely dissimilar bills and wings. The bill is sometimes much attenuated 

 and decur\-ed, as in /. cucnllatus, 

 while in mdcmocephalus and halti- 

 more it is stouter and straighter. 

 The tail is usually much graduated ; 

 in /. haltimorc and hullocki it is 

 only moderately rounded. These 

 last-mentioned species constitute 

 the genus ffijph antes. JIany of the 

 species have a naked space round 

 the eye, very e\ident in /. vulgaris, 



less so in melanoccphalus. I. vulgaris is peculiar in ha\inc 

 the throat pointed and lanceolate, as in the ravens. 



In view of the difficulties attendant upon the definition of subordinate 

 groups among the United States Idcrince, we propose to consider them all 

 under the single genus Icterus, leaving it for some one with more ingenuity 

 to establish satisfactory divisions into sub-genera.^ 



1 An attempt at division into .subgenera is as follows : — 



Icterus, bill stout, conical, the culinen and gonys nearly straight. Tail graduated. Species : 

 vulgaris, auduboni, mebinoccp/wlii.t. 



Xanthormis, bill slender, .sliglitly deetnved. Tail gi-.iduatcd. Species : wagleri, parisorum, 

 spuriiis, cncullotits. 



Hyphantes, bill stout, conical ; the culmen and gonys straight. Tail slightly rounded. Spe- 

 cies : ballimore, bullocli, abcilhi. 



We do not find, however, that these subgenera are very tangible, excepting Hyphantes, which 



Icterus blillocki. 



the feathers of 



