122 MR. PARKER ON SOME FOSSIL BIRDS 
The coarseness of these bones is well shown when the diploé is displayed (see Pl. XXX. 
figs. 10, 11 & 12), and the walls of the tibial diaphyses are a line and a half (one-eighth 
of an inch) thick in the stoutest specimens. 
The Ribs.—The coarseness of the bones, and their great size as compared with those 
of the tame species, are well seen in the three fragments of ribs; they are, altogether, 
one-fourth larger than their counterparts in the living Swans. 
The Ulna (Pl. XXX. figs. 4 & 5).—The diameter of the ulna, as seen in fig 5, is as 7 
to 5 compared with fig. 5a; and the strength of the shaft is well shown in fig.4. The 
oblong quill-knobs, confluent by means of an elevated ridge, are well shown to be precisely 
alike in the extinct and the tame species. 
The Femur (Pl. XXX. figs. 6, 7, 8, 9, 10 & 11).—These figures of the left femur, 
although not of the most massive specimens, give a good idea of the stoutness of this lost 
bird: its head, trochanter, shaft, and lower condyles are seen to be most exactly like those 
of the tame kind, save and except such intensification of the ridges and general surface- 
marking as is due to the origin and insertion of the muscles of a much mightier bird. 
Tibia (Pl. XXX. figs. 12, 15, 14 & 15).—This, again, is evidently the bone of a fe- 
male, as there are considerably larger specimens, although not so perfect, in the collec-. 
tion. Fig. 12 shows the strength of the shaft; fig. 15 is an anterior view of the distal end 
of the right tibia, showing the broad tendon-bridge and groove, the space for attachment 
of the fibula, and two depressions in the space for the precalcaneal knob, which are but 
faint in the tame kind. Fig. 14 shows the extent of the lower condyle as seen laterally - 
on the inside, and fig. 15 its division into an inner and outer lobe. 
Tarso-metatarse (Pl. XXX. figs. 16, 17, 18 & 19).—The length of this right shank 
is seen to be greater in proportion to its thickness than in the tame Swan; but their 
general agreement is most accurate. 
The low precalcaneal knob, the postcalcaneal ridges, grooves, and bridge, and the form 
and relative proportions of the lower bifid condyles are well seen. There is, however, a 
passage, shown in the head of the shank of the tame Swan (fig. 19a), which does not ap- 
pear in fig. 19: this mistaken foramen escaped me when examining the proof-plates ; it 
was made by me in the tame Swan’s bone for the purpose of syringing out the marrow. 
The bony bridge uniting the outer and middle condyles (figs. 16, 17, 18) is seen to 
correspond beautifully in the two birds; the perfection of the figures exonerates me 
from detailed description. 
Phalanges (Pl. XXX. figs. 20, 21 & 22).—There are only three phalanges which I 
can safely refer to the largest Swan; but they are very remarkable, being quite unlike 
what we see in the species of Swans still living; for fig. 20, as compared with fig. 20a, is 
seen to be full one-third thicker, and but little more than two-thirds the length. This 
is the case with the proximal phalanx of the great or middle toe; and the other two are 
quite similar in shortness and robustness. 
If this shortness of the toes be remembered, along with the fact that the shank is 
