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AVES. 



Tribe I. 



Beak straight, and slightly cleft; nostrils occupying nearly 

 one half its length ; toes moderate, the external ones & little 

 palmated ; thumb very short ; part of the head and neck naked. 

 There is only one genus — Grus (Crane) — but this has two 

 subgenera, viz., Psophia, Lin. (Trumpeter), where the beak is 

 shorter than in the other species, the head and neck clothed 

 only with down, and the circumference of the eye naked — and 

 the Ordinary Crane, where the beak is as long or longer than 

 the head. 



Tribe II. 



Beak stronger ; toes larger. One remarkable genus only — 

 that of the Ardea, Cuv. (Heron). Here a cleft of the beak 

 extends to beneath: the eyes ; nails long, the middle with in- 

 dented edge ; external web remarkable. Three subgenera, 

 but they are not well marked. 



Subgenus True Heron. 



Neck very slender and furnished towards the bottom with 

 long pendent feathers. 



Subgenus Bittern. 



Feathers of the neck loose and separated ; beak raised to- 

 wards the heavens when at rest. 



Subgenus Night-Heron. 



Port of the Bittern; beak thicker in proportion; some 

 sparse feathers upon the occiput. 



Tribe III. 



Besides a beak smoother than in the preceding, these have 

 webs nearly equal between the base of the toes. Two re- 

 markable genera — the genus Ciconia, Cuv. (Stork), with a 

 beak straight, thick, pointed and slightly cloven — and the 

 genus Platalea, Lin. (Spoon-bill) with a long beak termi- 

 nated by a disk flattened in the form of a spatula. 



FAMILY IV. LONGIROSTRES. 



Beak slender, long and weak, which restricts these birds 

 to a mere searching in the mud for Worms and Insects. Two 



