9194 Birds. 
metatarsal bones and the upper end of the right fibula. These are 
nearly equal in size to the corresponding parts of the skeleton of the 
Dinornis.s * * * 
“Tn neither the Dinornis nor the Apyornis is the metatarsus per- 
forated, as in Casuarius and many other birds, above the interspace 
between the outer condyles: that interspace is simply deeper, or 
curved higher in both. The outer trochlea, which is entire in both 
portions of the metatarsi in A\pyornis, is, in a marked degree, smaller 
than in Dinornis, as is also the inner trochlea, as far as one may judge 
from the posterior part which is preserved. The interspaces of the 
trochlez are wider posteriorly in A\pyornis, and the outer one is more 
angular at its upper end. The middle portion of the posterior surface 
of the lower third of the shaft of the metatarse in Zpyornis is more 
produced than in Dinornis, and a ridge is continued from it to each 
lateral trochlea, dividing the back part of the shaft above them into 
three surfaces; whereas the corresponding surface in Dinornis is simply 
flat from side to side. Above this part in Zpyornis the posterior sur- 
face on each side of the middle prominence is concave, and meets the 
anterior surface at a ridge which is narrowest at the outer border of the 
bone. In Dinornis both borders of the lower third of the shaft are 
thick and rounded. 
“The pyornis does not show any trace of the rough tract for 
attachment of a back toe, as in the Palapteryx robustus; in this respect 
it resembles the Dinornis. At six inches from the lower end the shaft 
begins to be concave along the middle of the fore part, the concavity 
deepening as it ascends; whereas in Dinornis the anterior median con- 
cavity of the shaft does not begin to appear until above the upper half 
of the bone. Jn this character the A;pyornis resembles the cassowary ; 
but it differs from the cassowary in the much narrower or sharper 
lateral margins of the shaft of the metatarsus. Like the cassowary, 
however, the breadth of the shaft is greater in proportion to that of the 
trochlea than in the Dinornis or Palapteryx. 
“Tt would be hazardous to conclude as to the length of the entire 
metatarse from the breadth of the distal end; for this is equal in 
Dinornis giganteus and Palapteryx robustus, whilst the length of the 
metatarse is 1 foot 6 inches in the one, and 1 foot four inches in the 
other. I think it more probable, however, that A:pyornis had a shorter 
rather than a longer metatarse than the Dinornis giganteus. 
“That its leg-bones were smaller is significantly indicated by the 
difference of size in the fibule. 
