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Show 448 PROF. HUXLEY ON THE CLASSIFICATION OF BIRDS. [Apr. II, In Merops the long and slender palatines are devoid of any posteroexternal elongations. The maxillo-palatines are slender and expanded at the end, as in Passerine birds, but they unite in the middle line with one another and with the ossified septum. As the vomer was absent in the specimen examined, I presume it to have been small and slender. Coracias has the vomer exceedingly attenuated ; and there are no basipterygoid processes. The spongy maxillo-palatines unite and form a thick transverse bar across the palate. Eurystomus resembles Coracias, but has broader palatines. It will be observed that all the genera of Birds which have been mentioned after the Parrots have their palates constructed upon the same principle as the Cuckoos. With one exception, basipterygoid processes are absent. The maxillo-palatines are united with one another, or with the ossified septum, or with both. The vomer is rudimentary, very small, and readily detached. In Picus viridis there are no basipterygoid processes. Each palatine bone is flat and obliquely truncated posteriorly, the posteroexternal angles not being produced. An elongated oval foramen, filled by membrane in the fresh state, occupies the middle third of its inner moiety, and is bounded, in front and internally, by a very slender bar of bone (fig. 30, c). This bar is continuous with the palatine by its anterior end. Posteriorly, in some specimens, it appears to be continued directly into the ascending process of the palatine ; but in one example I find it to terminate in a pointed end ; and the slender bar which corresponds with its apparent continuation in other specimens, is a perfectly distinct ossicle (Vo, fig. 30). Fig. 30. The palate of Picus viridis. a. The ossified septum, b. The transverse bar of bone connected with it. Vo. The ossicles which probably represent the vomers. Pmx Mxn Pl *' as before. ' "' ' - |