380 ON THE TRACHEA OF THE GALLING. [^P r - 1> 



as my facts go, this loop is found in the males only of the genera 

 Crax, Pauxis, and Mitua ; whilst in Penelope purjmrascens, P.cris- 

 tata, Pipile, and Aburria it is wanting in both sexes, it being present 

 in both sexes of Penelope jacucaca. In the males of Penelope 

 pileata and Ortalida albiventris 1 it is present; the females I have 

 not seen. 



The flattening of the trachea of the male Cracinse, excellently de- 

 picted (inverted) in Temminck's figure of the windpipe of Crax 

 alector 2 , is lateral or from side to side, so that the well-known an- 

 terior and posterior notching of the rings of the trachea is on the 

 thin edges of the flattened tube. 



In conclusion, it may be asked what light this detail concerning 

 the bifurcation of the trachea throws on the mutual affinities of the 

 genera of the Gallinee. It is very infrequently that the study of a 

 single organ justifies the formation of an ultimate classification of 

 any group ; and the windpipe of the Gallinse is not peculiar in this 

 respect. Several hints are to be derived from this investigation, 

 however, not unimportant in my estimation. 



Pavo seems to stand alone on account of the simplicity of its 

 bronchial bifurcation. 



There seems also to be a tendency for the majority of the Gal- 

 linse to fall into two divisions, a Coturnicine and a Phasianine ; in 

 the former of which it is the bronchial semirings which are most 

 specialized, at the same time that their anterior extremities are 

 pointed and produced inwards. In the latter group it is the last 

 tracheal ring that is most modified, its sides being always upturned. 

 Upon this assumption it is not easy to place the genera Qallus, Lo- 

 iphophorus, Meleayris, and Numida. The others fall into the follow- 

 ing order : — 



Coturnicine. Phasianine. 



Caccabis. Euplocamus. 



Argus. Pucrasia. 



Polyplectron. Ceriornis. 



Ithayinis. Phasianus. 



Lophortyx. Thaumalea. 



Oreor/yx. Crossoptilon. 



Arboricola. Lagopus. 



Mollulus. Tetrao. 



Ptilopachys. ( Meleayris ?). 



Coturnix. Perdix. 



It is surprising to see how much the lower end of the trachea of 

 the adult Gallus differs from that of Phasianus and its allies. A 

 study of the development of the windpipe of the Common Fowl — 

 which I have not had the opportunity of undertaking — would pro- 

 bably throw considerable light upon the subject. 



1 Vide Temminck, loc. cit. pi. viii. fig. 1. 



2 Loc. cit. pi. v. fig. 1. 



