356 NORTH AMERICAN BIRDS. 



AYe now come to the consideration, of three families of Oscine birds, of 

 pre-eminently dentirostral type, having certain commtjn characters by which 

 they are distinouishable, with but little difficulty, from all others. In their 

 close relationship it has been questioned by many whether they do not all 

 belong under one head, but they are more generally considered distinct. 

 The common characters, and those peculiar to each, are as tbllows : — 



CoMMOM Characters. Bill stout, and considerably hooked at tip, or with the point bent 

 abruptly downward ; with a deep notch, and .sornelitnes a tooth or lobe just behind the 

 notch; the tip of the lower mandible likewise frequently bent up, and with a notch 

 behind it. The nostrils lateral, the bristles of the mouth generally well developed. The 

 primaries are ten (except in a few Vireos), the outer from one fourth to one hall' the sec- 

 ond. Tail variable. Tarsi scutellate anteriorly ; sometimes with a tendency to division on 

 the lateral plates; hitherto not met with. Basal joints of toes more adherent. Seiiarated 

 from TurdidoB by greater adhesion of toes ; from Truylodytidw by notched and hooked 

 bill, etc. 



A. Basal phalanx of anterior toes abbreviated ; that of median toe decidedly shorter than 

 the basal of inner, or the two basal of outer, and adherent for its whole length on both 

 sides to the lateral (i. e. not free at all). Lateral plates of tarsus undivided, except at 

 extreme lower end. 



Vireonidae. Gonys more than half the length of lower jaw (from tip to angle of 

 mouth), usually longer than width of mouth, which is narrow. Bill conical, much 

 compressed, decurved at end and notched, but scarcely toothed. Frontal featliers 

 bristly and erect, or bent but slightly forward. Nostrils overhung by membrane. 

 Tarsus longer than middle toe and claw. Lateral toes generally unequal ; outer claw 

 reaching half-way along middle claw. 



B. Basal phalanx of middle toe about as long as the basal of inner, or the two bjisal of 

 outer; free externally, at least for about one third its length, internally for about one 

 half. Lateral plates of tarsus with decided tendency to subdivision (except in Myiades- 

 tin'f). 



Ampelidae. Gonys decidedly less than h.ilf the length of lower jaw, or than width 

 ol' mouth, which is very broad and deeply cleft. Bill triangular, much depressed, de- 

 curved at end and notched, with moderate though decided tooth. Frontal feathers 

 rather soft, scarcely bristly or erect. Nostrils overhung by membrane. Tarsus equal 

 to or shorter than middle toe and claw. Lateral toes nearly equal; outer claw reach- 

 ing only to base of middle claw. 



Laniidee. Gonys about half the length of lower jaw ; about equal to width of mouth. 

 Bill very powerful and raptorial, much compressed, with a strongly marked hook, 

 notch, and tooth at end. Frontal feathers very bristly, and directed forwards, so as 

 to conceal nostrils and base of bill. Nostrils with bony walls, except behind. Tarsus 

 longer than middle toe and claw, sometimes much scutellate on sides. Lateral claws 

 nearly equal ; outer claw reaching a Uttle beyond base of middle claw. 



