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R. FORBES founded this genus of Dinornithidae on remains of Moas of three distinct sizes as regards femora collected by him at Manitoto. Dr. Forbes has kindly placed these bones at my disposal, and the following summarises the results of my examination. I find that Dr. Forbes' original idea as to the distinctness of Palaeocasuarius is perfectly justified, as not only are his characters of the tibio-tarsus, as opposed to those in the other genera, correct, but the proportions between femur, tibio-tarsus and tarso-metatarsus are quite different to those of other genera. I give the proportions of the three bones in Palaeocasuarius elegans, Megalapteryx tenuipes, and Pachyornis elephantopus, which are the three most nearly allied genera:

The original diagnosis was as follows, being founded on the tibio-tarsus: "The tibio-tarsus differs from that of all other genera in being straighter and less twisted on itself, so that the position of the ridge forming the inner wall of the groove for the tendons of the extensor muscles run along the inner side of the bone as in Casuarius. As in the latter genus it takes a marked turn inwards and backwards before joining the epicnemial crest, while a line joining the centre point between the distal condyles and the epicnemial ridge leaves a considerable space between it and the wall of the groove. There is no intercondylar eminence in the intercondylar channel, and the orifice of the extensor foramen opens more longitudinally than in the other genera, and points downwards."

Type of the genus: Palaeocasuarius haasti Forbes.

Number of species: 3.

In the following descriptions of the three species I only rely on the measurements of the femora, as not all the other leg bones of the three species are available.