Portions of two molar teeth have been found, 1 inch 8 lines in greatest transverse diameter ; the tooth preserving the same size and shape through the whole length of the portion—viz., 11 inch. They resemble in shape those of the Orycterope, but are less regular and have not the same tubu lar tissue. Their microscopic texture appears not to have been analyzed ; it would be important to determine whether it resembled that of the teeth of the sloths or armadillos. The humerus differs from that of the ant-eaters and armadillos by its greater length in proportion to its breadth, and by the peculiar flattening from before backwards of its lower half, and especially at the condyles, above which it is expanded transversely by both external and internal supra-condyloid ridges. It is not perforated above the inner condyle, as the same bone is in both the Manis and Oryderopus. In the degree to which it departs from the type of the ant-eaters it approaches that of the Megatherioids and sloths—viz., in its relative length, flattening at the distal end, and the imperfo rate character of that end. The radius also presents a sloth like character in its greater proportionate length, which exceeds that of the humerus ; and in the compression of its lower slightly-expanded end. In both the Pangolin and Orycterope, the radius is shorter than the humerus. The ulna differs likewise from both that of the Pangolin and Orycterope, and still more from that in the Armadillos by the much smaller development of the olecranon, whereby, again, it more resembles that of the sloths. The femur is relatively
longer and more slender than that of the terrestrial and fos sorial Edentata ; it has not the third trochanter which charac terizes it in the Orycterope, nor so marked a development of the great and small trochanters as in the Pangolin. In the flattened form of the shaft of the femur, and the position of the rotular surface near one side of the distal end, it resembles the femur of the Megatherium and Mylodon. It is shorter than the humerus ; whereas, in both the Pangolin and Oryc terope the femur is longer : in this respect the femur of the Macrothere resembles that of the sloths. The great width of the popliteal space dividing the condyles is an edentate and more especially a megatherioid character. The internal con dyle is much broader than the external one, as it likewise is in the Megatherioids ; it is certainly with the femur of the latter family of the Edentata, rather than with that of the Proboscidians or Pachyderms, that one should compare the femur of the Macrothere : it is not so long or so slender relatively as in the sloths. The tibia is much shorter than the femur, and in the expansion of its proximal end and its rela tive length to the femur it resembles that of the Megatheroids more than that in the Pangolin or Orycterope ; it was not anchylosed to the tibia as in the Armadillos, Glyptodons, and Megatherium, but remained a distinct bone, as in the and sloths.