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Show 1880.] MR. E. W. WHITE ON CHLAMYDOPHORUS TRUNCATUS. 9 (y) The lateral edges of the dorsal chitinous shield are represented as though forming a continuous wave-line, whereas these lateral edges are sharply serrated. (d) In some drawings the body is figured as almost nude, or at most covered only with scanty short hair; the truth is, the body is covered throughout, even down to the extremities of the humerus and femur, and beneath the dermo-skeleton to the dorsal ridge, with a thick silky downy mantle. (e) In all drawings that have come under m y observation the eye is delineated as distinctly visible-whereas, in nature it is rudimentary, besides being completely covered by the intermingling of the fringe and mantle. (£) In all published representations there is a general deficiency of apparent solidity aud roundness towards the truncated portion; the body is too m u c h flattened. The fact is, the basal rings of the dorsal coat-of-mail increase in circumference until they coincide with the outer edge of the truncated extremity, the sections gradually rising from an elliptic to a circular form ; further, the projection of this slightly convex truncated extremity is very exactly a sector of a circle, the centre of which is in the point whence issues the tail, the whole of this truncated armour-plate forming a very hard, solid, bonelike structure, which at once suggests the use to which, in m y opinion, it is devoted, viz. to act as a rammer to consolidate the sand and fill up the entrance to its burrow from the inside and thus prevent the ingress of its enemies. (rj) The nature of the ground frequented is generally represented as rocky; now a Chlamydophorus on a rocky eminence is an anomaly, as it is only found on and in medanos (sand-dunes), or in their proximity, the characteristic vegetation of which is low thorny brushwood and cacti. W h e n walking, the Chlamydophorus plants both the fore and hind feet on the soles, and not on the contracted claws, as is the case with the Ant-eater, carrying its inflexible tail, which it has no power to raise, trailing along the ground and much inclined downwards from the body. As it commences to excavate, the fore feet are first employed; and immediately afterwards, supporting its body on the tripod formed of these and of the extremity of the tail, both hind feet are set to work simultaneously, discharging the sand with incredible swiftness. The burrows, which are never left open, usually have but slight, if any, inclination to the horizon. Although analogy and form would seem to indicate it, I never could detect the tail aiding in the operation of excavation; in fact, its inflexibility precludes this idea : the only use of the flattened extremity appears to m e to be, to furnish it with a more secure point of support in the shifting sand. Sluggish in all its movements except as a fodient, in which capacity it perhaps excels all other burrowing animals, the Chlamydophorus performs the operation of excavation with such celerity that a m an |