THE RED-KNOBBED CURASSOW. 



Crax varrellii. 



Although we have seen but a single individual of this 

 breed in the adult state and bearing the characteristic 

 marks of the species, we have little hesitation in regard- 

 ing it as distinct from all the Curassows that have 

 hitherto been brought to Europe. Its distinguishing 

 characters, it is true, are not very remarkable, but they 

 are perfectly obvious to the eye ; they are taken from 

 the modifications of an organ which seems in the pre- 

 sent family to afford the best distinctive marks, and 

 they are quite as decided as those which have l)een 

 employed to characterize the other allowed species of 

 the group. A knowledge of the internal organization, 

 and particularly of the structure of the trachea is, how- 

 ever, still wanting to determine this point with certainty ; 

 for it is possible that the long domestication of some of 



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