CUCULID^ — THE CUCKOOS. 459 



The three families next in order are those generally known as the Zijgodac- 

 tyli, in their more restricted sense, that is, ha\"ing the toes arranged in pairs, 

 two before and two behind. In tlie present case the anterior toes are the 

 inner and the middle (the second and third), the posterior being the hinder 

 and outer (the tirst and fourth) ; where, as is sometimes the ease, a hind toe is 

 wanting, it is the first, or the hind toe proper. 



By this definition we exclude the Trogonidcc, the Bucconidce, and the 

 Galbuilidcr, which likewise have the toes in pairs, but in whicli they are dif- 

 ferently combined. 



The North American families, the Cuculidce, the Ficidce, and the Psittacidce, 

 are defined as follows : — 



A. Upper mandible not movable nor hinged. Tar.sus with tran.sver.?e scutellse. 

 Bill without a naked skin, or cere, at the base ; lower mandible much longer 

 than deep, the end not truncated. 



a. Tongue short, and not extensible ; not barbed at the point. 



Bill hooked or curved at tip ; not constructed for hammering. No 

 nasal tufts ........... Cuculidas. 



h. Tongue long and cylindrical, and generally capalile of great extension ; 

 barbed at the point. 



Bill not hooked, but nearly straight ; strong, and constructed for ham- 

 mering. Thick nasal tufts at base of the bill (except in the Nudinares). 



Picidce. 



B. Upper mandible movable or hinged. Tarsus without transverse scutelUe. 

 Bill with a naked skin, or cere, at the base ; lower mandible not longer than 

 deep, its end truncated. 



c. Tongue short and thick, fleshy. 



Bill enormously large, much curved, the upper mandible hooked, both 

 much arched .......... Psittacidce. 



