Folia Historico-Naturalia Musei Matraensis - A Mátra Múzeum Természetrajzi Közleményei 21. (1996)

Ulna In the case of the length of the ulna the order of the species is similar what we saw in the case of the radius or humerus. The ulna of the Merlin is also strikingly short, but not as short as in the case of the radius. The length of the ulna of the greatest male specimens exceeds that of the smallest Lesser Kestrel. The size of the ulna of the Eleonora's Falcon is considerably greater than in any other species, but the Hobby and Kestrel overlap considerably. The length of the ulna of the Red-footed Falcon (except the Eleonora's Falcon) overlaps with all the other species, the Lesser Kestrel overlaps with the Red-footed Falcon and Merlin (Plate XTV, Figure 1). In the Hobby and Merlin the sexes separates quite well, in the Kestrels they do not. The transverse measures of the ulna of the Hobby, due to its large size, clearly separates from the of the Red-footed Falcon and Lesser Kestrel, with a small overlap also from the Merlin, and if we distinguish the sexes even from that of the Kestrel. Similarly the Kestrel separates from the Lesser Kestrel (see the PW, PH, DT values), but from the Red-footed Falcon do not separates, even if the sexes are treated separately the diameters overlap. In the case of the single measured Eleonora's Falcon specimen the width of the corpus is very large, but the width of the distal end of the bone (DT) is relatively small (Plate XIII, Figure 2; Plate XIV, Figure 2; Plate XV, Figure 1). With the help of the ratio values only the Kestrels and true Falcons can be separated, the GL/DT and GL/PH ratios are especially adept for this purpose. Morphologically it is characteristic that the ulna of the Hobby is robust, the ends of the bones are large, the corpus ulnae is thick, and widens strongly towards the proximal end of the bone both in ventral and cranial view. In the Merlin in its ratios the size of the ends of the bones and the width of the corpus ulnae is similar to the Hobby, but the corpus does not widen at all towards the proximal end of the bone in ventral view, and in cranial view only less (Plate XXXVII, Figures 6-7). The longitudinal axis of the ulna in the Hobby and Merlin is more curved (ventral view), than in the Kestrels. The proximal section of the ulna in the Merlin is more curved than in the Hobby (Plate XXXVII, Figures 6-10). In the Kestrels the ends of the bones are smaller, the corpus ulnae is thinner, and in ventral view only slightly widens toward the proximal end. In cranial view though, the corpus stronger widens toward the proximal end in the Kestrel than in the Red-footed Falcon. The curve of the longitudinal axis of the ulna is smallest in the Red-footed Falcon and Lesser Kestrel (ventral or dorsal view), but this characteristic is hard to detect, and there are exceptions (Plate XXXVII, Figures 8-10). The olecranon is relatively largest in the Merlin, and hence the GL/PH ratio is lowest in this species(Plate XIII, Figure 2). The ratio of the width and height of the proximal end of the bone (PW/PH) is lowest in the Merlin and highest in the Kestrel. The latter is explained by the fact that the proximal end is relatively wider in the Kestrel than in the Red-footed Falcon and Lesser Kestrel. In the Red-footed Falcon and Merlin the dorso-cranial edge of the cotyla dorsalis (proximal end of the bone) is more elevated than in the Kestrel and Hobby. The edge of labrum condyli at the distal end of the bone in the Red-footed Falcon connects to corpus ulnae more evenly, smoothly than in the Kestrel and Hobby where the connection is more abrupt, there is a break (caudal view). This break is the strongist in the Merlin (Plate XXXVII, Figures 6-10). The distal end of the bone is the narrowest in the Red-footed Falcon at the condylus dorsalis in dorso-ventral direction, and the widest in the Merlin (caudal view). 29