262 
PROFESSOR OWEN ON THE FOSSIL MAMMALS OF AUSTRALIA. 
Already, since writing the above, evidence has reached me, in the last Packet from 
Sydney, which I shall probably be not the only one to hail as undesigned witness to 
what I deem the truth of the matter. 
Amongst the fossils obtained by Professor Thomson and Mr. Krefft from the breccia- 
caves of Wellington Valley were several ungual phalanges, some of which, equalling or 
surpassing those of a Lion, were compressed, the vertical exceeding the transverse dia- 
meter, and being considerable in proportion to the length : these phalanges are curved 
and pointed, but the point is more or less blunted or broken, apparently after interment. 
They supported a claw, and in most there are traces more or less plainly discernible of 
a bony sheath which bound or strengthened the attachment of the base of the claw. 
These specimens, at present, I know only by photographs of the natural size. 
Plate XIII. fig. 12 is of one of these ungual phalanges, 1 inch 9 lines in length, 1 inch 
3 lines in basal depth. The articulation («) occupies the upper half of the basal surface ; 
it is concave and divided by a median vertical ridge, adapting it to the pair of convexities 
on the distal end of the penultimate phalanx. A strong tuberous process ( b ) for the 
insertion of the flexor tendon projects from the lower part of the basal half of the bone. 
A ridge (c) anterior to the joint may indicate the attachment of the sheath broken away. 
Figure 14 gives an under view of this phalanx, showing the breadth of the apophysial 
part of the base, and the compressed character of the decurved claw-bearing part of the 
phalanx. 
Figure 13 is a side view of a similar phalanx, 1 inch 8 lines in length, 1 inch in basal 
depth. The upper part of the articular surface (a) is more produced, or better preserved, 
than in figure 12 ; and the indication of the sheath ( c , c) is more considerable and begins 
more in advance. The insertional tuberosity (b) also extends rather more forward. 
In the next photograph (ib. fig. 11) the bony basal claw-sheath (c, c ) is evidently pre- 
served ; its anterior margin is 1 inch 3 lines in advance of the hind part of the phalanx; 
but this, as well as the under surface of the back part, appears to be mutilated. One 
half or side of the sheath has been broken away, exposing the core of the claw (d), the 
pointed termination of which is better preserved than in the preceding specimens. 
From these specimens may be inferred a spelaean animal with subcompressed decurved 
pointed claws, equalling or exceeding those of the Lion or Tiger in size, but supported 
by phalanges resembling those of Thylacinus , Dasyurus, and the Opossums in being 
non-retractile, or wanting the characteristic low position of the joint in the sheathed 
claw-bones of placental Felines, but resembling those phalanges, rather than the non- 
retractile ones of the Marsupials above mentioned, in the proportion of depth to length 
and breadth. 
A claw may be adapted to pierce, retain, and lacerate (as, for example, the large 
sheathed one of Myrmecojphaga jubata), and be used as a weapon against a mammal of 
equal or superior size only in defence (as when the great Anteater causes the death of 
its assailant the Jaguar by the tenacity of its grip). So, likewise, may the claws of the 
Megatherioids have been put to such occasional defensive uses against their probable 
