Proceedings of the Royal Society of Edinburgh, Section B: Biological Sciences
The presence upon the ulna of many birds of a row of smaller or greater tuberosities, their variety in size and conformation, and the presence of other appearances on the surface of the ulna suggested that an investigation of these variations and of the development of the structures might yield points of interest.
Owen (1848) was apparently the first (we have been unable to consult Brandt's paper, quoted by Gadow) to draw attention to these ulnar markings, related to the quills of the secondary remiges. In that year he published a schematic outline drawing of the avian forelimb. Neither in this nor in a subsequent publication (1849), however, did he describe the linear series of markings on the ulna shown in the drawing; but in 1866 he stated that “on the ulnar and anconal sides of the shaft are the rows of quill-knobs (in Raptores) for the secondaries; the anconal row is most marked in longipennate Natatores, and is the only row in many birds.” He mentioned also that this character is wanting in the flightless and some other birds. Pl. I, fig. 1, will be seen to correspond closely with his description.