MESSES. A. AND E. NEWTON ON THE OSTEOLOGY OE THE SOLITAIEE. 345 
has already been not only elaborately described by Dr. Melville and Strickland 
(opp. citt .), but also compared by them with the corresponding bone of Didus. It is 
accordingly unnecessary here to say more about it than to remark that the large series 
of specimens in our possession forbids us from coinciding in the generalization propounded 
by Strickland (Trans. Zool. Soc. iv. p. 196) as to the “inner or longest calcaneal 
process” in Pezophaps being considerably less developed than in Didus. This process, 
now regarded* as the head of the third (anchylosed) metatarsal, does not project poste- 
riorly (it is true) so much as in Didus ; but this fact appears to us to be in consequence 
of the heads of the second and fourth (anchylosed) metatarsals being expanded laterally 
rather than antero-posteriorly. In like manner, and for the same reason, we are unable 
to confirm Strickland’s generalization as to the three trochlese at the lower extre- 
mity being placed more nearly in the same vertical plane in Didus than in Pezophaps ; for 
in this last the large series of examples shows that the angle formed by joining the 
centres of the three trochlese (of course the only mode of accurately testing the obser- 
vation) is much more obtuse in the smaller (female X) specimens than in the larger 
(male V). In this case, if any stress is to be laid on Strickland’s inference (ut supra cit.), 
it would follow that the larger (male X) examples of Pezophaps did not run so quickly as 
ordinary examples of Didus , while the smaller (female 1) attained a greater speed. The 
orifice of the calcaneal canal is absolutely smaller in Pezophaps than in Didus, a fact 
apparently arising from the greater thickening in the former of the “ calcaneal processes.” 
For the rest we may safely leave this bone as already accurately and sufficiently de- 
scribed. 
The posterior metatarsal (Plate XX. figs. 104, 105), of which fifteen specimens are 
contained in the collection, is one of the few bones we have not had the opportunity of 
comparing with the corresponding part of Didus. Judging, however, from the figures 
and a model of the celebrated Oxford specimen, it would appear to be more massive and 
to present a smoother surface, the furrow for lodging the flexor tendons of the hallux 
not being so deep, and the whole bone is less crooked. The proximal articular surface 
is more convex in the middle than it would appear to be in Didus ; but its lower portion 
is roughened just as is said to be the case there. The styloid process is much less deve- 
loped than it would seem to be in Didus, and on the surface which is twisted forwards 
it becomes almost flush with the trochlea, so that its boundaries are not strongly defined ; 
on the other hand the pit on the inner extremity of the trochlea is to all appearance as 
deep as in Didus. Generally this bone in Pezophaps would seem to be longer, which is 
of course in proportion to the increased length of the lower extremities. 
Among the phalanges, of which the collection contains in all one hundred and fifty- 
specimens, there is wanting the second and third of the inner, and the second, third, 
and fourth of the outer toes. The first, or proximal phalanx of the hind toe (Plate 
XX. figs. 106, 107) seems to be a good deal stouter relatively than it is in Didus, 
* Cf - Gegenbattr, Arch, fur Anat. und Physiol. 1863, pp. 450-472 ; Untersuchungen zur vergleichenden 
Auatomie der Wirbelthiere (4to, Leipzig : 1864), pp. 93-108, pi. vi. 
MDCCCLXIX. 3 a 
