Note 724 — Chapter XVIII

One fragment of a bone, apparently of an ulna, retained a row of small eminences, probably the points of attachment for the quills of the secondary feathers of the wings. This specimen would appear to have a decided reference to ornithic structure, but it was transferred to the British Museum, and is not now to be seen.

[725] See Quart. Geol. Journ. vol. ii. p. 96, &c.; and Owen’s Monograph on Chalk Reptiles, 1851, p. 80, et seq. It is to be hoped that the eminent microscopists, Mr. Bowerbank and Professor Quekett, may be enabled before long to elucidate the intimate structure of pterodactylian bone; which, although of an essentially reptilian type, has characters of its own, offering some resemblances to bird-structure, that have not yet been fully described. Some specimens of bones from the Wealden (for instance, the specimen figured in Geol. Trans. 2d ser. vol. v. pl. xiii. fig. 6, and Geol. Journ. vol. iv. pl. i. fig. 9,) exhibit under the microscope an intimate structure resembling that seen in bird-bone, in contradistinction to that characteristic of reptilian bone. But until we are better acquainted with the microscopic structure of the osseous tissue of the Pterosaurians, and are in possession of more perfect specimens of bones, it cannot be satisfactorily determined to what extent the class of Birds existed in the country of the Iguanodon.