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

separates the Merlin and Hobby from each other and from the Kestrels, and more or less the Red-footed Falcon and Lesser Kestrel is also separated from each other (Plate ХХХП, Figure 2). The crista plantaris medialis and lateralis are only present on the proximal part of the phalanx. These are considerably longer and higher in the Merlin than in the Hobby, and hence the phalanx in lateral view gets thicker stronger in the former than in the latter. These cristae in the Kestrels corresponding to the shorter phalanges are a lot shorter, but are still present, and hence in lateral view the phalanx gets the widest in proximal direction in these species (Plate XLV, Figures 16-18). The hollow between the cristae is shallower in the Red-footed Falcon than in the Kestrel. On the dorsal side of the capitulum phalangis between the condyli there is a tuberculum. This tuberculum intercondylare dorsale is greatest in the Hobby, almost as big in the Merlin. In the Red-footed Falcon it is small, but still visible, and in the Kestrel it is usually completely missing (Plate XLV, Figures 16-18). In the Kestrel the diameter of the capitulum phalangis is greater than in the other species, and its dorsal edge in lateral view extends well above the dorsal line of corpus phalangis (in the other species it is not so) (Plate XLV, Figures 16-18). In the Red-footed Falcon the edges of the condylus lateralis and cond. medialis are sharper than in the Kestrel. Summary Falco subbuteo: - the phalanx is especially long and relatively thin, - the crista plantaris medialis and lateralis are shorter and lower, - the tuberculum intercondylare dorsale is the largest in this species, - the dorsal edge of capitulum phalangis is not elevated above the dorsal line of the corpus (lateral view). Falco columbarius: - the phalanx is long and relatively thin, - the crista plantaris medialis and lateralis are high, - the tuberculum intercondylare dorsale is smaller, but well visible, - the dorsal edge of capitulum phalangis is not elevated above the dorsal line of the corpus (lateral view). Falco tinnunculus. - the phalanx is relatively short and thick, - the ends of the bone (especially the capitulum phalangis) are large sized, - the tuberculum intercondylare dorsale is missing, - the dorsal edge of capitulum phalangis is elevated well above the dorsal line of the corpus (lateral view). Falco vespertinus. - the phalanx is short, - the ends of the bone are smaller, especially so the capitulum phalangis, - the edges of condylus lateralis and medialis are sharp, - the tuberculum intercondylare dorsale is almost invisible, - the dorsal edge of capitulum phalangis is not elevated above the dorsal line of the corpus (lateral view). Falco naumanni: - the phalanx is very short, and relatively thick, - the capitulum phalangis is smaller. 59