BY C. W. DE VIS. 
1279 
froQi the side of the radial condyle at its mid-length. A distinct 
tubercle is wanting in the Alcedinidpe {Dacelo, Halcyon), but in 
these it is substituted by a tumid expansion of the end of the 
radial ridge which runs outward to join the radial condyle at its 
anconal end. In all the genera of the Anatidfe (save Dendrocygna) 
available for comparison, the tubercle is absent, and in Nyroca its 
place is occupied by a depression at the foot of the radial I’idge, 
similar to but of smaller size and feebler definition than that of 
the fossil. The radial condyle is broad, regularly elliptical, obtuse 
and very feebly recurved at its palmar end. It is separated from 
the ulnar condyle by a narrow groove, and its axis forms an acute 
angle with that of the shaft, a further prohibition against I’eferring 
the bone to the Falconidae or Strigos. The ulnar condyle is rela- 
tively large, ovate, but little contracted at its junction with the 
i-adial, and is di.stinctly separated from the ulnar tuberosity by an 
ol)lique groove continued from the palmar to the anconal surface. 
Its convexity is both longitudinally and transversely continuous, 
a feature separating it from Corvidae and other Passeres. The 
separation of the ulnar condyle from the adjacent tuberosity by a 
grooved sui'face occurs, but with less decision, in Alcedinidee. In 
D'lcelo the palmar end of the groove is crossed by a ridge from 
the endoconrlylar tubercle to the ulnar condyle. Moreover, in this 
genus the >ilnar condyle is greatly constricted by a deep inteiTOtular 
notch. In the Anatidm, except CJienoph and Dendrocygna, the 
condition of this part of the fossil is clearly identifiable, and in 
none more so than in Nyroca. The depression on the palmar 
surface is sub-oval in shaije. It commences at the endocondylar 
tubercle, and runs obliquely proximad to the radial edge of the 
shaft at its expansion. The form and extent of this depression 
do not however constitute a character to be relied on as an index 
of atllnity. 
The characters, positive and negative, of the fo.ssil in (piestion, 
ytoint conclusively to the Anatidm as its family, and to Nyroca as 
its generic status. 
It was a distinctly larger sp(;cies than its Australian reprcren- 
tative in tnodern days, being one-eighth moi'e in tlio width (d’ the 
81 
