OCR Text |
Show 1894.] IN THE BRITISH MUSEUM. 117 (6) The rotular surface is very broad and flat, and makes an angle of about 90° with the inferior intercondylar surface instead of passing into it by a gentle curve. The intercondylar fossa is slightly marked. The upper pneumatic foramen is present as in AS. titan, and, the floor of the popliteal fossa being broken away, it can be seen that the inferior foramina opened into a large air-chamber. There is also a pneumatic foramen about the middle of the rotular surface, which is not found in AS. titan. The nutritive foramen on the posterior surface of the shaft is single, in the femur above referred to AS. titan there are two; but since this is not the case in some of the more imperfect femora belonging to the same species, it is merely an individual variation. This femur may possibly belong to AS. maximus or to either of the recently named species, AS. cursor and AS. lentus (4). In any case, as was remarked above, the differences between it and the femur referred to AS. titan appear to be of generic value; and if this be so, then there is evidence of the existence of a third genus, since the recently named Mullerornis seems to include only slender forms of comparatively small size. Until, however, it is definitely known whether the femur of the type species of ASpyornis resembles that of AS. titan or the one just described it would be imprudent to establish a new generic name. The evidence necessary for the decision of this question is probably in the hands of M M . Milne-Edwards and Grandidier, and a full description and figures of the magnificent collection recently briefly noticed by them, especially of the skulls and sterna, will be anxiously awaited. From the same locality there are several fragments, including the distal ends of three tibio-tarsi, which appear to belong to AS. maximus. A right tarso-metatarsus with the upper end above the interosseous foramina broken away may also be provisionally referred to the same species ; it is, however, slightly smaller, measuring 6-3 cm. across the narrowest part of the shaft in comparison with 6*9 cm. in AS. maximus. If AS. medius should be found to be a distinct species, this bone may possibly belong to it. In form it closely resembles the tarso-metatarsus of AS. maximus figured by Milne-Edwards aud Grandidier (3), aud, like it, differs from the tarso-metatarsi from the centre of the island mainly in the fact that the shaft contracts from side to side above the trochleas more gradually and to a slightly less extent\ From Itampulu-Ve and Amboulisatra are several portions of the skeleton of a much smaller form, possibly that recently named Mullerornis agilis by Milne-Edwards and Grandidier (4). These include the distal ends of several tibio-tarsi (Plate X V . fig. 1), which closely resemble the same boue of the larger forms in their 1 This specimen may belong to the species recently named M. cursor by Milne-Edwards and Grandidier. |