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Show 1891.] SAUROGNATHISM OF THE PICI. 123 cranial base in these forms, that he suggested a separate group for the Pici, viz. the Celeomorphce. But in characterizing this group, he was, from an insufficient supply of material, led into several errors,-errors of omission and errors of commission,-which have since been appreciated by the avian morphologist. Professor Huxley held that in the W o o d peckers "the vomers are very delicate rod-like bones, which in some cases, at any rate, remain permanently separate." It will be observed that he makes no reference to that median bone which is seen to lie between the palatines in some species, and which Parker afterwards designated as the " medio-palatine." It would be superfluous for m e to enter upon the question here of the enormous, and upon the whole beneficial, influence this masterly and opportune memoir has had upon the study of avian structure and taxonomy. Later on Professor Garrod called into question the conception of these parts as arrived at by Professor Huxley1. Garrod remarked that " Professor Huxley, in his paper ' O n the Classification of Birds,' has entered into considerable detail respecting the Woodpecker's palate, and from not finding a vomer present, and observing the peculiar longitudinal bony spicula connected with the inner edges of the palatine bones, opposite to and behind the fenestra? they assist to enclose, is led to think that these spicula are the rudiments of the vomer, which has not ossified across the middle line. But in carefully prepared skulls they look much more like the inner edges of the imperfectly ossified palatines, as they are connected completely with them at both ends. Further, in most of the specimens of Gecinus viridis and its allies that I have had the opportunity of examining, I have found a median bone, situated between the palatines, and supported like a vomer on the basisphenoid rostrum, at the anterior end of its broader portion. This bone is small, and shaped very much like a spear-head with the tip directed forwards, whilst posteriorly it gradually becomes fibrous and tends to bifurcate, but not in the ossified part. It does not extend backwards quite so far as the pterygo-palatine articulation." It is evident that Garrod saw the vomer of the Pici in the median bone which Professor Huxley had overlooked, and construed the spicula given off by the palatine bones, not as vomers, but as palatine spurs of processes. Next appears the beautiful monograph of Professor W . Kitchen Parker, entitled " O n the Morphology of the Skull in the Woodpeckers (Picidse) and Wrynecks (Yungidae)," which was read before the Linnean Society of London in April 1874. It is illustrated by five superb 4to plates coloured, giving enlarged views of the skulls of several Woodpeckers, lynx, &c. In this work Professor Parker essentially adopted the views of Huxley in the premisses and amplified them. The saurognathism of the Pici, however, evidently still had its doubters and opponents, for in the work just quoted Professor Parker 1 Garrod, A. W., " Note on some of the Cranial Peculiarities of the Woodpeckers," Ibis, 1872, pp. 357-60, October 1. |