BY C. W. DE VIS. 
1281 
Nyroca australis, Gld. 
(PL XXXIII. Hg. 3.) 
Between a second coracoid of a Nyroca and that of N. australis 
there are difterences which might be interpreted as specific, but 
wliich, on the other hand, may be reasonably thought within the 
range of individual variation; and since difference of geologic time 
is not of itself sufficient proof to the contrary, this bone is 
provisionally referred to the extant species. It is the first 
instance, within the writer’s personal experience, of identity or 
even of affinity so close, between a recent and postpliocene verte- 
brate from the Darling Downs.* 
Anas elapsa, n.sp. 
(PL XXXIII. figs. 4a, 4b, 4c.) 
Left tibia . — In this bone the procnemial ridge is produced from 
the tibial side of the rotular process to a length exceeding its 
depth, and is upwardly inclined. In the Falconidm and Striges, 
Alcedinidse and P.sittaci, a peculiar facies is given to the head of 
the tibia, as seen from above, by the straightness of its anterior 
border resulting fi’om the feeble development of the rotular process 
and ectocnemial ridge. As an almost ecpially characteristic form of 
the part in Passeres, the anterior border curves forward at both 
ends, forming the edge of a deep median sulcus between the 
greatly expanded pro- and ectocnemial ridges. This is well 
illustrated by Memira. In some pigeons also, e.g., Megaloprepia, 
the junction of the ridges forms a median notch — in others, Macro- 
j>ygia, Goura, the notch is on the inner side adjacent to the 
rotular process — Imt in these birds the ridges are comparatively 
feeble. With a similar disposition a great expansion of the ridges 
takes place in the Kallidas and Anseres, and in the latter the elon- 
gation of the procnemial ridge in y>roportion to its depth reaches 
its greatest extent. That of the fossil is eijiinently natatorial in 
aspect, and its anserine rather than ralline afiinity is supporti^d by 
the absence of any scar for a fii’st metatarsal, and by the almost 
Vide Postscript at the end of tliis paper (p. 129*2.) 
