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

Diagram shows the width of the sternal end of the bone in proportion to the length of the coracoideum. The longitudinal axis of the coracoideum is less curved in the Merlin and Red-footed Falcon than in the Hobby, Eleonora's Falcon, Kestrel and Lesser Kestrel. Hence the line of the facies articularis sternalis meets the longitudinal axis in a larger angle (gets near to the right angle), than in the latter species. The omal end of the coracoideum in the Kestrel is relatively small, but wider than that of the Merlin. The facies articularis sternalis is wide. The lateral edge of the sternal end has the most flattened arch in this species (Plate XXXVI, Figure 12), and hence the facies articularis sternalis is often wider than the width of the and of the bone measured at the hypothesized processus lateralis. In the Red-footed Falcon the omal end is long, the basal part of processus procoracoideus is connected lower to the corpus than in the Kestrel. The lateral edge of the sternal end is most curved in this species (Plate XXXVI, Figure 13). The coracoideum of the Lesser Kestrel is very small, and exceptionally short. Consequently the corpus is thickest proportionally to its length in this species, and the sternal end of the bone is wider then in the Kestrel and Eleonora's Falcon. Summary Falco subbuteo: - the omal end of the bone is extremely large, the corpus is thick, - the lateral edge of the sternal end of the bone is usually strongly curved, sometimes even the processus lateralis is also formed, - the longitudinal axis of the coracoideum is curved, especially so at the joint of the omal end of the bone and the corpus. Falco columbarius: - the coracoideum is long, thin, - the omal end of the bone is narrow, - the sternal end of the bone is narrow. Falco eleonorae. - the coracoideum is exceptionally large, the corpus is thick, - the omal end of the bone is large, - the sternal end of the bone is wide. Falco tinnunculus. - the omal end of the bone is short, wide, - the longitudinal axis of the coracoideum is most curved in this species, - the arch of the lateral edge of the sternal end of the bone is most flattened in this species. Falco vespertinus: - the coracoideum is long, the corpus is thin, - the omal end of the bone is long, narrow, - the longitudinal axis of the coracoideum is less curved in this species, - the lateral edge of the sternal end of the bone is strongly curved, the processus lateralis is forming. Falco naumanni: - the coracoideum is very small and short, - the corpus is relatively the thickest in this species, the sternal end of the bone is widest. 24