383 
p. 61, Pl. XIV. s)', not “the extensor tendon of the toes.” Professor Marsh admits 
that the lower part of his fossil tibia “ has little of the marked inward curvature cha- 
racteristic of swimming birds, but is so straight that its median plane, if continued, 
would divide the trochlear surface nearly equally ” (ib. p. 207), He further states that 
* the outer margin of the canal is low and obtuse, as in most of the Gallinaceous birds” 
(ib. p. 206), that “on the lower surface of the inner condylar ridge there is a shallow 
notch, resembling in shape and position that in the tibia of some Gulls” (ib.), and 
that “the shaft curves forward slightly just where it begins to expand above the lower 
condyles, closely resembling in this respect the tibia of the Turkey” (ib. p. 207). 
Nevertheless on this portion of bone is founded the genus Laornis, of the order 
Natatores, bearing “‘a strong resemblance in many respects to the Lamellirostres and 
also to the Longipennes, but differing essentially from the typical forms of both these 
groups.” 
With all respect to the learned Professor of Paleontology in Yale College, I would 
express the strong wish felt, with myself, by many of my fellow labourers in that science, 
that he would accompany his descriptions, notices, and names of new genera and species of 
extinct animals with figures, of the natural size, of the fossils on which such are founded. 
Casts would be still more acceptable for European comparisons. In relation to the 
subject of the present memoir it is plain that if the fossil tibia, “‘nearly as large” as 
that of a Wild Swan, prove to be really anserine, it cannot be referred to the genus 
Cnemiornis of 1865. 
The species representing this anserine genus was about the same size as, or, rather, 
exceeded, its contemporary, also now extinct, the ralline Aptornis defossor. Both equalled 
in bulk the smaller species of Cassowary. The height of the back of Cnemiornis above 
the ground probably exceeded 2 feet; and the length of its body from beak to tail must 
have been at least 3 feet. 
DESCRIPTION OF THE PLATES. 
PLATE CI. 
Fig. 1. Side view of skull of Cnemiornis. Fig. 6. Side view of skull of Cereopsis. 
Fig. 2. Back view of ditto. Fig. 7. Back view of ditto. 
Fig. 3. Upper view of ditto. Fig. 8. Upper view of ditto. 
Fig. 4. Under view of ditto. Fig, 9. Under view of ditto. 
Fig. 5. Upper view of mandible. Fig. 10. Upper view of mandible. 
Fig. 11. Back view of base of maxilla of Cnemiornis. 
Fig. 12. Prefrontal portion of cranium of ditto. 
1 See also ‘ Anat. of Vertebrates,’ ii, (1866) p. 108, and Alphonse Milne-Edwards, ‘ Oiseaux Fossiles de la 
France,’ 1867, 4to, pl. 7. figs, 1 d& 2, 13, 13" (tibial antérieur). 
