OCR Text |
Show 1878.] PROF. A. H. GARROD ON INDICATOR MAJOR. 933 In Indicator the vomer is less ossified than in the Capitonidae above mentioned, and is smaller ; the fork is slenderer and has longer limbs, which, however, quite typically join the well separated maxillo-palatines (which advance but slightly beyond the inner margins of the palatine bones) at their posterior angles. As the Ramphastidae have to be mentioned so frequently in connexion with the genus under consideration, it may be useful to refer to the vomer of this family. By Prof. Huxley it js included among his Coccygomorphae, in which the vomer, if present, is pointed anteriorly. Prof. Huxley further remarks ** that in Bamphastos " the antero-internal angles of the palatines not only meet, but are united by bone." But close examination demonstrates a large tabular truncation of the anterior extremity in the Rimphastine vomer, which I cannot help thinking Prof. Huxley interpreted as a median osseous bridge formed by the (supposed) blending of the antero-internal angles of the palatines. Figure 2 represents the vomer of Fig. 2. Palatal aspect of the truncated vomer of Bamphastos arid, with the posterior parts of the palatine bones retained in union with it. Ramphastos arid, freed from its surroundings. It does not send forward limbs to join the maxillo-palatines [which are those of the desmognathous Capitonidae inflated], but helps by its terminal expansion to complete, by contact or ankylosis with the palatine on either side, the posterior wall of a cavity in the dried skull, bounded laterally and superiorly by the inflated and infused maxillo-palatines, anteriorly by the nasal septum together with ossifications in the nasal cartilages associated with it. In the ' Transactions' of the Linnean Society2 Prof. Parker describes the vomer of Bamphastos toco as double, it being composed of a smaller posterior and a larger anterior bone, the truncated nature of which I a m not able to infer from the account given. The Capitonidae, the Ramphastidae, and Indicator are intimately associated, therefore, so far as the vomer is concerned. Nevertheless the proportionally great length of the limbs of the vomerine fork in the last-named form, and the considerable separation of its small 1 P. Z. S. 1867, p. 444. 2 Linn. Trans. 2nd ser. vol. i. p. 127. PROC. ZOOL. Soc-1878, No. LXI. Gl |