Word Study
aves
CIDE DICTIONARY
aves, n. pl. [L., pl. of avis bird.].
The class of Vertebrata that includes the birds. [1913 Webster]
" Aves, or birds, have a complete double circulation, oviparous, reproduction, front limbs peculiarly modified as wings; and they bear feathers. All existing birds have a horny beak, without teeth; but some Mesozoic fossil birds (Odontornithes) had conical teeth inserted in both jaws. The principal groups are: Carinatæ , including all existing flying birds; Ratitæ , including the ostrich and allies, the apteryx, and the extinct moas; Odontornithes , or fossil birds with teeth." [1913 Webster]
"The ordinary birds are classified largely by the structure of the beak and feet, which are in direct relation to their habits. See Beak , Bird , Odontonithes ." [1913 Webster]
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