298 
BON ASA. HEATHCOCK. 
Generic Character. 
Kostnim breve, basi plumo- 
sum, supra convexum, ver- 
sus apicem incurvatum. 
Nares basales, plumulis ob- 
tectas. 
Collum utrlnque pennis plu- 
rimis elongatis, alulam si- 
mulantibus, instructum. 
Pedes tetradactyli mutici ; 
tarsi hlrsuti. 
Cauda rotundata. 
Ala, breves, rotundatas. 
Beak short, feathered at the 
base, above convex ; to- 
wards the tip bent do^v^l. 
Nostrils basal, covered -wntli 
feathers. 
Ncch furnished on each side 
with many feathers, re- 
sembling a wing. 
four- toed, spurless; tarsi 
haiiy. 
Tail rounded. 
Wings short and rounded. 
Attagen. Bris.'i. 
Tetrao. Linn., Gmel., Lath., Tern., Vieil. 
Bonasa. Briss. 
1 HE birds of this genus are distinguished from 
those of the preceding in having the feathers of 
the neck elevated on eacli side like a mantle : 
tlieir legs are only feathered to the toes, the latter 
])eing naked and scaly. Two species only are 
known, both of which are natives of America. 
