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NUMBER 89
Cor.
Cpm. o
Tbt.
Tmt.
Ph.
DI
Ph. 1
DM
Ph. 1
Dill
Ph. 2
Dill
Ph. 1
DIV
50
I
100
I
150
I
• Geronticus eremita, standard
O Threskiornis spinicollis
• Threskiornis aethiopicus
% Threskiornis solitarius
FIGURE 3.—Ratio-diagram of dimensions of long bones of Threskiornis solitarius compared with those of a male
T. aethiopicus (USNM 558412), and of T. spinicollis (mean of two males, USNM 347785,429720). The standard
is a Geronticus eremita (UCB Lyon 1974-1). Coracoid measurement is of internal length; for other bones, measurement
is of total length. When measurements are not known, successive points are united by dashed lines.
(Cor.=coracoid, Cpm.=carpometacarpus, DI-DIV=digits I-IV, Ph.=pedal phalanx, Tbt.=tibiotarsus, Tmt.=
tarsometatarsus.)
width and depth of the proximal and distal ends and of the shaft
are almost always larger than in those two species. This indicates
that the Reunion Ibis must have been of comparable size
but was much heavier. The quadrate (Figure As, Table 4) is
much stronger than in living forms; thus, the head of the bird
must have been larger. The two mandibular rami are wider at
the level of the symphysis (Figure An-o), and the bill must
have been more robust.
In Threskiornis solitarius the acrocoracoid is wider on the
anterior face (Figure lk-l). Only a proximal part of the humerus
is known (Figure 4p), i.e., where the head forms a lobe
above the capital groove; the distal outline of this area is much
more rectilinear in T. aethiopicus. The two known carpometa-
200
carpi have an accessory foramen at the distal part of the symphysis
between the alular and the major metacarpals (Figure
Aq), and this foramen is absent in T. aethiopicus. The pisiform
apophysis is preserved on only one specimen; it projects further
internally than it does in T aethiopicus or T. spinicollis.
The alular metacarpals and the pisiform apophyses end in
rough protuberances, as can be seen in birds that use their
wings to fight. In T. solitarius the minor and major metacarpals
are fused over a longer distance, at both proximal and distal extremities,
than in T. aethiopicus, but the same is true in T. spinicollis.
On the tarsometatarsus, the trochleae are more splayed
and are disposed on a less-curved line than in T. aethiopicus.
The tarsometatarsi of T. solitarius (Figure Ic-e) look very