122 CLASS AVES. 



the use of it is decidedly preferable. Now the natives of 

 Brazil give the name of Guan to the Penelope, which forms 

 our present subject. It has been preferred by M. Temminck 

 to that of Yacoti, given by Buffon, because he finds two dis- 

 tinct species confounded under the latter denomination. That 

 described by BufFon must be referred to the Guan of Ed- 

 wards, and to the Penelope Cristata of Latham. The other, 

 which is the Yacou of Bajon, is the same bird as the Pene- 

 lope Cumanensis and Pipile. The addition of Sonnini to 

 the article of Yacou of BufFon is partly referable to our pre- 

 sent Guan, and partly to Penelope Pipile. A second reason 

 which made M. Temminck suppress the Yacou, was, that all 

 the known Penelopes among the Indians of America bear the 

 names of Jac, Jacu, Jacuhu, or Yacuhu. 



This Guan is the largest of all the known Penelopes, mea- 

 suring in total from twenty to thirty inches ; the throat is 

 naked, and from it hangs a flowing membrane, of a fine red 

 colour. This membrane, extremely ductile, is elongated or 

 contracted, according as the bird is agitated or not. As it 

 forms but a single piece with the naked skin of the throat, 

 and is double as large as the turkey's, the bird can with- 

 draw it entirely. The feet are red. 



The female scarcely appears to differ from the male except 

 in the reflexions of the plumage, the shades of which are 

 more tinted with reddish. The feathers of the crest, those 

 of the neck and mantle, are also bordered with white. 



The chick has no nudity on the temples, nor at the throat. 

 The head and sides of th^ neck are covered with a reddish 

 down ; from the occiput and all the length of the hinder part 

 of the neck, is a broad stripe of marron down ; two more 

 marron stripes accompany it on each side. 



M. Temminck found in three male individuals of this spe- 

 cies that the tvibe of the trachea, after having accompanied 

 the oesophagus as far as the clavicles, mounts over the right 



