87 
thicker and stronger bone, and yet has more signs of immaturity. We in like manner 
associate together f 7, f 8, f 17, as not varying beyond a line from the length of eight 
inches. 
In the first four femora, f 1, f 2, f 3, f 12, enumerated in the table, there is a more 
regular gradation of size. ‘The left femur, f 12, is eleven inches, and the shaft of a 
right femur, f 4, so precisely corresponds in circumference and other proportions as to 
leave no doubt as to their similarity in length, and render it highly probable that they 
belonged to the same bird. The femora f 2 and f 3 were thirteen inches in length ; 
and the shaft f 1 indicates a femur of at least sixteen inches in length. 
In an Ostrich the circumference of the femur, of the tibia, and of the metatarsus is 
respectively five inches three lines, four inches three lines, and three inches seven lines. 
In an Emeu the circumference of the same bones is respectively three inches seven lines, 
three inches four lines, and three inches. 
From these analogies we may conclude that the shaft of the femur f 1, with a cir- 
cumference of seven inches and three lines, may have belonged to a Dinornis with the 
largest tibia whose circumference is six inches six lines, and with the tarso-metatarsal 
bone whose circumference is five inches six lines, the proportionate thicknesses of 
these bones to each other being intermediate in their degrees to those presented by the 
same bones in the Ostrich and the Emeu. It must be remembered that the relative 
length of the femur and metatarsus is very different in the Dinornis from that in existing 
Struthionide, the Apteryx excepted; but, according to the above collocation of the 
femur, tibia and tarso-metatarsus of the largest Dinornis, the tarso-metatarsus exceeds 
the femur in length by 24 inches in this species, which I have named Dinornis giganteus. 
The femur f 2 presents a similar correspondence with the tibia ¢ 2; but its excess of 
length over the tarso-metatarsus m 3 renders it very improbable that they could belong 
to the same species, especially when the difference in their circumference is added, 
that of the femur being six inches one line, that of the metatarsus four inches three 
lines; besides, the distal articulation of the tibia ¢ 2 is obviously too large for the arti- 
culation of the metatarsus m 3. The femur f 12 offers the required correspondence 
with the metatarsus m 3 of the Dinornis struthoides, which exceeds the length of that 
femur by one inch, and is consequently but a little shorter in proportion than in the 
largest species. 
The tarso-metatarsus is proportionally still shorter in the third species (Dinornis didi- 
formis), to which I refer the femora f7, f8, f17, the tibix #3, #4, £5, 8, £9, £10, and 
the tarso-metatarsal bones m4,m5,m6. The tibia, according to this allocation, being, 
like that of the gigantic Dinornis, little more than twice the length of the femur, we 
may with great probability associate the shaft of the tibia, which, when restored, gives 
a length of twenty-five inches, with the femur of the Dinornis struthoides measuring 
eleven inches in length. 
The proportions of the three principal bones of the leg in the Ostrich, the Emeu, the 
