MANUAL OF NATURAL HISTORY. 43 



on forehead, lateral margins generally ser- 

 rated; nostrils placed near middle and ex- 

 posed ; tarsi short, strong ; outer toe fre- 

 quently capable of being turned backwards ; 

 wings rounded. 



24. FAMILY. Hornbills (Bucerontidse). Bill very 

 large, long, broad at base, curved and com- 

 pressed to tip, upper mandible generally sur- 

 mounted with protuberances of various shapes 

 at base, which advance more or less on fore- 

 head ; lateral margins serrated ; tarsi short, 

 strong. 



III. ORDER SCANSORIAL-BIRDS (Scansores). 



Feet particularly formed for climbing, having two 

 toes before and two behind ; tarsi usually very short. 



1. FAMILY. Toucans (Rhamphastididse). Bill very 



large, light, cellular, long and compressed, 

 curved to tip, margin serrated ; tarsi short ; 

 toes long ; wings rounded. 



2. FAMILY. Parrots (Psittacidse). Bill very strong, 



short, compressed, deep, upper mandible form- 

 ing a short curve from base to tip, which 

 beads considerably over and is much longer 

 than lower, lateral margins of upper mandible 

 sometimes toothed ; nostrils placed in a cere ; 

 tarsi short, strong, and rounded. 



3. FAMILY. Barbets (Capitonid^). Bill thick, di- 



lated at base, which is generally furnished 

 with stiff bristles, compressed towards tip, 

 culmen gently curved to the tip which is 



