. Transactions of the Zoological Society of London . , entoglossal; , basihyal (first basibranchial) ; , cerate-branchial. articulation for the basihyal (basibranchial 1) (), and laterad to this the outerangles are produced into short backwardly-directed processes. The first basibranchial () (basihyal) is a short bar of bone, the thinner lateralborders of which seem to have been broken away. Its dorsal surface is concave frombefore backward, and on its anterior half from side to side also; ventrally it is convexfrom before backward. The anterior end bears a double surface f
. Transactions of the Zoological Society of London . , entoglossal; , basihyal (first basibranchial) ; , cerate-branchial. articulation for the basihyal (basibranchial 1) (), and laterad to this the outerangles are produced into short backwardly-directed processes. The first basibranchial () (basihyal) is a short bar of bone, the thinner lateralborders of which seem to have been broken away. Its dorsal surface is concave frombefore backward, and on its anterior half from side to side also; ventrally it is convexfrom before backward. The anterior end bears a double surface for articulation withthe entoglossal, separated by a slight ridge, which at its ventral extremity is producedinto an anteriorly-projecting prominence. Posteriorly there are two irregular surfacesfor the ceratobranchials, meeting at an angle of about 120°. The first basibranchial isnot prolonged backward into a urohyal, nor does it, as far as can be seen, bear anysurface for the articulation of a distinct median element: if such were present it must. 68 ME. C. W. ANDEEWS ON THE SKULL AND have been small and have articulated with the bases of the ceratobranchials ().These are thin, slightly curved rods of bone, the anterior ends of which are enlargedand bear the surface for the articulation with the first basibranchial. The posteriorends are also slightly expanded and terminate in convex facets, apparently for unionwith another element. In the Albatross the entoglossal is relatively very much smaller, the first basibranchial(basihyal) broad and short, and prolonged backward into a long urohyal, so that thearticular surfaces for the ceratobranchials are widely separated. In Grus the entoglossal is very long, slender, and unossified; the first basibranchial(basihyal) is also long and slender, but, as in the fossil, the ceratobranchials articulatewith two contiguous surfaces on its hinder end, and the uroglossal is distinct andarticulates between the bases of the ceratohyals. I
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Keywords: ., bookcentury1800, bookdecade1830, booksubjectzoology, bookyear1835
