OCR Text |
Show 380 ON THE TRACHEA OF THE GALLING. [Apr. 1, as m y facts go, this loop is found in the males only of the genera Crax, Pauxis, and Mitua ; whilst in Penelope purpurascens, P. cristata, Pipile, and Aburria it is wanting in both sexes, it being present in both sexes of Penelope jaeucaca. In the males of Penelope pileata and Ortalida albiventris' it is present; the females I have not seen. The flattening of the trachea of the male Cracinae, excellently depicted (inverted) in Temminck's figure of the windpipe of Crax alector2, is lateral or from side to side, so that the well-known anterior 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 Gallinae. 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 Gallinae is not peculiar in this respect. Several hints are to be derived from this investigation, however, not unimportant in m y 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 Gallinae 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 Gallus, Lo-phophorus, Meleagris, and Numida. The others fall into the following order:- COTURNICIN^E. PHASIANINE. Caccabis. Euplocamus. Argus. Pucrasia. Polyplectron. Ceriornis. Lthaginis. Phasianus. Lophortyx. Thaumalea. Oreortyx. Crossoptilon. Arboricola. Lagopus. Rollulus. Tetrao. Ptilopachys. (31eleagris1). 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 probably throw considerable light upon the subject. 1 Vide Temminck, loc. cit. pi. viii. fig. 1. 2 Loc. cit. pi. v. fig. 1. |