182 



tion"*, so much as it will expose " the fallacious train of reasoning which had led them 



astray "f. 



Should Thylacoleo be permitted to rest, after the facts and inferences from the fossil 

 evidences at my command, in the section of diprotodont Marsupials, with Plagiaulax, 

 amongst the predaceous feeders on flesh, and not with Hyjpsiprymnits amongst the 

 harmless Herbivora, it will only be further proof of the worth and truth of the principle 

 which CuviEB laid down as our guide in such dark routes in Palaeontology. 



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 1 deem the truth of the matter. 



Amongst the fossils obtained by Professor Thomson and Mr. Kkefft from the brcccia- 

 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 X. fig. 12 is of one of these ungual phalanges, 1 inch 9 lines in length, 1 inch 

 3 lines in basal depth. The articulation (a) 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 11 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 13 ; 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. 12) 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, JDasyurus, and the Opossums in being 

 non-retractile, or wanting the characteristic low position of the joint in the sheathed 

 * X. p. 350 ; XI. p. 433. t Id. ib. 



