| OCR Text |
Show 432 MR. F. E. BEDDARD ON THE [June 3, The relationships of the bird from the point of view of the structure of the syrinx are somewhat doubtful. It is, in any case, very different from that of Podiceps, of which I propose to give a more detailed description in another paper. As to the Colymbidae, I have in my possession a syrinx of Co-lymbus septentrionalis which agrees in all essentials with that of Fig. 1. Syrinx of Podica senegalensis, front view ; nat. size. Podica; the only difference is that the bronchial semirings are rather more numerous, and are hardly divided anteriorly by membranous interspaces; I do not mean to imply that they are fused, but they are so close together as to leave only the merest chink between adjacent rings. The resemblance then of Podica senegalensis to Colymbus septentrionalis in respect of the syrinx is very close, but there are many Rails which show an equally close resemblance to both, so that the syrinx is unfortunately not very useful as a diagnostic character. § 5. Osteology. Brandt [7, p. 199] remarks that Podoa and Podiceps agree closely in the form of the skull, but that it is broader and more vaulted posteriorly in Heliornis : it is clear from his figures (pi. xii. figs. 1, 2, 3) that Heliornis offers no marked points of difference from Podica. In another section of the same paper (p. 155), Brandt comments upon certain points of resemblance between Podoa and the Stegano-podes; there is, however, no detailed comparison of the skeleton in any of these types. In spite of these alleged resemblances, Heliornis is placed with Fulica into a separate Family (Podiceps being placed with Penguins and Auks in another) of the six into which the Natatores are divided. Giebel [6] has described, without figures, but in a more thorough fashion, the osteology (and to a certain extent the soft parts also) of Heliornis surinamensis, comparing it with the Grebes on the one hand, and with various genera of Rails (Fulica, Gallinula, Porzana) on the other. |
