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Show 122 ON REMAINS OF JEPYORNIS IN THE BRITISH MUSEUM. [Feb. 6, result of convergence resulting from similar conditions of life, that though the great massiveness of the skeleton (pachyostosis) is characteristic of both families, it is attained in quite a different manner in the two cases. This conclusion would certainly seem to be supported by the bones here described. In the femora, for instance, apart from their great difference of form, the large upper pneumatic foramen, the numerous smaller ones opening into the popliteal fossa, and the great development of the bony reticulum are characters entirely wanting in Dinornis. Such points of structure as these appear to be of more importance in determining affinities than the mere external form of the bones, which may be supposed to vary more readily with changes in the conditions of life; for it is difficult to understand how such differences of structure could arise in two closely related forms, since the same end appears to be attained in the two cases in different ways. The conclusion to be drawn from this is that the divergence between the two families must have occurred before the characteristic pachyostosis had been acquired. In their recent paper (4) Milne-Edwards and Grandidier have given a brief description of the skull, which, as far as it goes, does not seem to afford much evidence in favour of the supposed close relationship with Dinornis; nevertheless, at the close of their communication the authors, as in their former paper, assert their belief that there is really such a relationship, and suggest the former existence of a southern land-connection to account for it. Perhaps when a complete description with figures of the skull, sternum, and pectoral girdle have been published, it may be possible to arrive at some definite conclusion concerning this interesting point. List of papers referred to. 1. BIANCONI, G. G.-Numerous papers published in the ' Memorie dell' Accademia delle Scienze dell' Istituto di Bologna' between 1861 and 1873. 2. BURCKHARDT, B.-" Leber ASpyornis." Palaontologische Abhandlungen, Neue Polge, Bd. ii. Heft 2. Jena, 1893. 3. E D W A R D S , A L P H . MILNE-, ET ALE. GRANDIDIER.-" Nouvelles Observations sur les Caracteres zoologiques et les Affinites naturelles de VASpyornis de Madagascar." Annales des Sciences naturelles (Zoologie), serie 5, vol. xii. Paris, 1869. 4. EDWARDS, A L P H . MILNE-, ET A L P . GRANDIDIER.-"Observations sur YASpyornis de Madagascar." Comptes Bendus de l'Acad. d. Sci. t. cxviii. p. 122. Jan. 1894. Paris. 5. FURBRINGER, MAX.-Untersuchungen zur Morphologie und Systematik der Vdgel. II. AUgemeiner Theil, pp. 1463-6. Amsterdam, 1888. 6. GEOPPROY ST.-HILAIRE, ISIDORE.-" Note sur des ossements et des asufs trouves a, Madagascar dans des alluvions modernes, et provenant d'un Oiseau gigantesque." Comptes Bendus de l'Acad. d. Sci. t. xxxii. p. 101. Paris, 1851. |