| OCR Text |
Show 1904.] FROM MADAGASCAR AND EGYPT. 167 reception of the so-called middle trochlea of the tibia. The upper pax-t of tlxe anterior face of the shaft is deeply concave owing to the posterior position of the upper end of the middle metatarsal; this concavity runs about three-quarters of tlxe way down the shaft, and even below this the antexior face is slightly grooved for- the adductor tendons. Tire inter-osseous foramina open at tlxe same level anteriorly, and immediately beneath them is the sixxgle lax-ge txrberosity for tlxe insertion of the tendon of the tibialis anticus. O n the posterior surface of the bone, the upper end of tlxe third metatarsal forms tlxe bulk of the large talon, consisting of a px-o-minent ridge on the outer side and a small tuberosity on the inner, sepax-ated by a shallow groove for the tendons. The main ridge of the talon is continued down tlxe upper three-fourths of the trihedral shaft, of which it forms tlxe posterior angle. In section, the middle portion of tlxe shaft is triangular, the sides of the triangle beixxg concave and tlxe concavity of the anterior face being the deepest. A little above the distal articulation the shaft is convex in front and slightly concave behind. The middle tx-ochlea is much the largest of the three axxd extends considex-ably beyond the inner one, which in size and form closely resembles the outer, much more nearly, indeed, than is the case in JEpyornis. Just above the notch between the outer and middle trochlea?, the bone is perfox-ated by two foramina, one above the other but close together: of these the upper one (add.) pierces the bone and opens on the palmar aspect at the postex-ior end of the channel between the two trochlea?, the other opens in the middle of tlxe same channel; the upper or posterior- of these perforations probably transmitted tlxe tendon of the adductor cligiti externi, but tlxe function of tlxe other is unknown to me. In a note on some remains of JEpyornis in the Trixxg Museum published some years ago*, 1 ventrrr-ed to suggest that Mullerornis rudis, the metatarsal of which is said to be perforated by the tendon of tlxe adductor cligiti externi, should on that account be referred to a new genus, Flacourtia. If the presence of this character were really of generic value taken alone, the present species should likewise be referred to Flacourtia ; but since the presence or absence of this perfoi-ation seems to be of vex-y vax-iable occux'rence, it will be better to refer all the small, lightly built ^Epyornithida1 at present known to one genus, Mullerornis, at least till some more valid distinctioxxs are found, which m a y vexy well happen when tlxe skulls and skeletons of the various species are known. So far as can be seen, the thickening of tlxe bones (pachyostosis), though of course much less in degree than in JEpyornis, is of precisely tlxe same kind as that described by Burckhardt in* the case of JEpyornis hildebrandti, and differs from the type found in the Dinornithida3, in which tlxe bones are much more solid and heavier. * Novitates Zoologicae, vol. ii. p. 25. Tring, 1895. |
