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Show 1890.] THE STRUCTURE O F PSOPHIA. 331 project inwards of the palatines. They differ from those of Grus and Fulica in being convex, and not concave, on the outer side. In these points, Psophia agrees with Chunga and Ocydromus. In Rhinochetus and Eurypyga the maxillo-palatines are thin curved plates entirely invisible when the skulls are looked at from below. In Numenius, Metopidius, and GZdicnemus their structure is much like that of the last-mentioned genera. Aramus connects Grus with Psophia. The lachrymal bone in Psophia is large and its descending process is club-shaped and swollen ; it nearly comes into contact with the rather thick prefrontal process of the ethmoid. On the whole it appears to m e that this bone is most similar to that of Chunga and (Edicnemus l. In Fulica, Aramus, Ocydromus, Aramides, and Grus the descending process of the lachrymal nowhere near touches the piefrontal process of the ethmoid. It becomes fused with it in Parra, Hydro-phasianus, Metopidius, and Numenius. The palatines of Psophia, as Parker has remarked2, come nearest to those of the Cranes ; I find that Aramus (which must be regarded as a Crane), QZdicnemus, and Numenius have palatines which are not unlike those of Psophia and the Cranes. Ocydromus, Fulica, Porphyrio, Parra so far differ that the anterior half of each palatine is very much narrower than the posterior. Before proceeding to discuss the affinities of Psophia as indicated by the skull, it will be convenient to clear the ground by contrasting several of the more typical Gralline forms, which have, it appears to me, been wrongly associated together. The Cranes do not show so many points of resemblance to the Limicolae as to warrant their inclusion in the same group, while QSdicnemus, usually assigned to the Limicolae, differs from both. Grus. The supraorbital ridges are rounded off and the impressions for glands only just furrow their margin. Lachrymal does not join ectethmoid. Occipital foramina present. Basipterygoid processes absent4. Hamatopus. The supraorbital ridges are sharp and the depressions for supraorbital glands are conspicuous. Lacbrymal completely fused with ectethmoid, forming a ring 3. present. present. QZclicnemus. The supraorbital ridges are sharp. No depression for glands. Lachrymal articulates with ectethmoid, forming a ring; lachrymal also prolonged so as to nearly reach jugal. absent. absent. 1 In a specimen of OJJ. bistriatus I found this bone ankylosed with the margin of the orbit. 2 Loc. cit. p. 509. J I find that Garrod (" O n the Anatomy of Aramus scolopaccus," P. Z. S. 1876, p. 275) has laid stress upon this characteristic feature of the Limicoline skull. 4 According to Huxley they are present in Grus virgo. |