156

134

of Din. curtus, wanting therefore one-fourth of its mature dimensions, as shown in
Pl. XXVII. figg. 3 & 4, would exhibit the same imperfect coalescence of the proximal
ends of the primitively distinct metatarsals which chracterizes the above-cited tarso-
metatarsal (m.2.) of the young Din. giganteus. In the tarso-metatarsal bone of the
Din. curtus, figured in Pl. XL. fig. 6, the coalescence is as complete as in the corres-
sponding mature bones of the Din. didiformis not in size only, but in shape and propor-
tions, the shaft being broader in proportion to the length of the bone.

The information derived from the specimens of Dinornis transmitted to this country
since the publication of my first (1839) and second (1843) memoirs in the 'Transactions
of the Zoological Society,' vol. iii., may be summed up as follows :-

Confirmation of the deductions as to the rudimental development of the wings in the
genus Dinornis, by the discovery of the keel-less sternum, and the evidence it affords of
the small size of the coracoid bones.

Confirmation that the species of this essentially terrestral genus were heavier and
more bulky birds in proportion to their height, more powerful scratchers, and less swift
of foot than the Ostrich*, but in different degrees, according to the species.

Indications of an affinity to the Dodo in the shape of the cranium ; but with evidence
of a lower development of the cerebrum, whence the Dinornis may be inferred to have
been a duller and more stupid bird.

Confirmation of the species --
1. Dinornis giganteus.
2. ------------- ingens.
3. ------------- struthoides.
4. ------------- dromioides.
5. ------------- didiformis.
6. ------------- otidiformis.

* A correspondent of the 'Polytechnic Journal' for July 1843, commenting on my description of the fragment
of the femur of the Movie, in the 'Proceedings of the Zoological Society', November 1839, objects : "Neither
does its femur furnish reason to conjecture that it was swift or slow of foot." (p. 7) I have not however drawn
any absolute conclusion as to the rate of locomotion of the Dinornis. My remark was merely comparative, as
respected the Ostrich. In the large existing bird, which is remarkable for both its swift and long-sustained
course, the femur is filled with air, like that of a bird of flight. In the fragment of femur which first indicated the
genus Dinornis, I found the cavity of the bone much smaller than in the Ostrich, with evidence that it had con-
tained marrow ; the bony walls being thicker, the cancellous structure more extensive, and the whole bone heavier
than in the Ostrich. The femur of the Dinornis therefore did furnish not merely 'reason for conjecture', but grounds
for legitimate physiological conclusion, that that extinct bird was heavier and less swift-footed than the Ostrich.

The proportions of the other bones of the leg which have since arrived establish the accuracy of the conclusion
deduced from the structure of the femur ; the metatarsal bones being in the Dinornis one-third shorter and
thicker in proportion than in the Ostrich, thus rendering the legs more like those of the Apteryx, and conse-
quently more like those of the Gallinaceous birds than in any of the existing large Struthious tribe.