126 PROFESSOR OWEN ON THE GENUS DINORNIS, 
g. Obturator notch. r. Pelvic disk. 
s. Sacral vertebra (s 1, in Pl. XV. fig. 2, marking the anterior articular surface of the 
first centrum). 
t. Interacetabular cavity. u. Postrenal cavity. 
v. Ilio-ischial plate or deck-like production. 
z. Prezygapophysis (marking, in Pl, XIV. fig. 1, that of the first sacral vertebra). 
1-20 indicate the sacral vertebra from before backward. 
62. Tlium. 63. Ischium. 64, Pubis. 
In the restoration of the skeleton (in which I have taken the vertebral formula of 
Ocydromus) the Aptornis defossor, with the neck bent and head supported as in the 
ordinary standing position of the bird, would be about 3 feet in a straight line from 
the top of the head to the soles of the feet; the length, in a straight line, from the 
end of the beak to that of the tail would be about 2 feet 10 inches. The chief depar- 
ture from the ordinary form of the Coots is seen in the shorter and more robust 
proportions of the tibiee and metatarsal segments of the legs, in which feature Wotornis, 
amongst recent Rallines, offers the nearest approach to Aptornis, 
DESCRIPTION OF THE PLATES. 
PLATE XIV. 
. Side view of pelvis of Aptornis defossor, nat. size. 
. Front or under view of sternum of ditto, nat. size. 
. Back or upper view of sternum of ditto, nat. size. 
. Side view of sternum of ditto, nat. size, 
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PLATE XY, 
Fig. 1. Upper view of pelvis of Aptornis defossor, nat. size. 
Fig. 2. Under view of pelvis of ditto, nat. size. 
PLATE XVI. 
Fig. 1. Restoration of skeleton of Aptornis defossor. th nat, size. 
Fig. 2. Skeleton of Ocydromus australis, 4th nat, size, 
