344 ON THE TRACHEA OF MANUCODIA ATEA, ETC. 



This is well known to occur in both sexes of Cygnus ferus : it is 

 likewise the case in both males and females of C. buccinator, C. ameri- 

 canus (according to Macgillivray, Sharpless, &c.), and C. bewicki 

 (Tarrell). 



[In Cygnus olor, C. immutabilis (Macgillivray), C. nigricollis, and 

 C. coscoroba the trachea is quite simple in both sexes.] 



According to Tarrell, in Cygnus atratus there is a slight downwardly- 

 directed loop of the trachea in the interclavicular region. 



Earn. G-ETJID^E. 



The genus G-rus, as a rule in both sexes, possesses a convoluted 

 trachea, which usually enters the carina sterni, which it may excavate to 

 its posterior extremity. The amount of convolution varies much in 

 different specimens of the same species. 



Species examined. 



Grus cinerea. c? ? (Tarrell, &c.) 



- antigone. d (Tegetmeier). $ . 



- americana. $ (cf. Roberts, Am. Nat. 1880). 



- carunculata. tf , $ . 



- leucogeranos. tf , $ . 



P. Z. S. 1882, As regards these two species, it appears from Prof. G-arrod's MS. notes 

 p. 353. that the male of G. leucogeranos has a convoluted trachea, only slightly 

 folded in the carina sterni, extending in it for less than half its extent * ; 

 whilst in the female " there was formed a genu of small size, that does 

 not enter the carina sterni" The female of G. carunculata examined 

 had a trachea as well convoluted as the most developed forms of G. ameri- 

 whilst in the male the condition was as in the female of G. leuco- 



geranos. 



Grus australasiana. <$ [? $ ]. 



- canadensis. $ . 



In Tetrapterycc paradisea, according to Tarrell and Tegetmeier, as well 

 as in Anthropoides virgo according to Parsons and Tarrell, the trachea is 

 convoluted, but does not enter the carina sterni, being contained in a 

 special groove developed along the anterior margin of that bone. 



[In both species of Balearica the trachea is known to be quite simple ; 

 and the same is probably true in Aramus scolopaceus.'] 



* The observations of Mr. A. O. Hume (cf. Tegetmeier's ' Cranes,' p. 39, &c.) do not, 

 therefore, always hold good for this species. 



