36 MANUAL OF NATUKAL HISTOKY. 



with reticulated scales ; claws but slightly 

 curved, blunt ; crop prominent. 



2. Family.— Falcons (Falconidse). Head clothed; 



eyes sunk ; bill more or less curved from base ; 

 cutting margins toothed, festooned, or sinu- 

 ated ; tarsi variable in length, usually covered 

 in front with large scales, seldom reticulated ; 

 claws much curved, very acute. 



II. SUB-ORDER. — Nocturnal Eapacious Birds 

 (Nocturni). 



Eyes large, placed in front, surrounded by a circle 

 of radiating feathers. 



3. Family. — Owls (Strigidse). Head large ; bill 



short, much hooked, upper mandible entire, 

 lower notched ; tarsi and toes more or less 

 feathered. 



II. OBDEB. — Perching Birds (Passeres). 



Feet more or less formed for clasping the branches 

 of trees ; toes generally three before and one behind, 

 sometimes two and two. Very numerous; divided 

 into the Fissirostral, Tenuirostral, Dentirostral, 

 and Conirostral tribes. 



I. SUB-ORDER. — Eissirostral Birds (Fissirostres). 



Gape wide, extending beneath eyes ; feet variously 

 formed ; tarsi nearly always short. 



1. TBIBE — Nocturnal Fissirostral Birds 

 (Nocturni), 



Eyes very large ; plumage dingy, soft, downy. 



