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Show 236 MR. W. V. LEGGE ON PKDIONOMUS. [Apr. 8, Thus the peculiarity of L. americanus consists in the development of the feet relatively to the body generally, as contrasted with other species. Although only weighing 3 lb. in New Brunswick, against 6\ lb. in southern districts, with a corresponding diminution in the dimensions of the body, the feet yet retain fully as great development in one as the other. L. timidus, with an average weight of 8 lb., and length 26 inches, has a hind foot only 5| inches long; whilst L. variabilis, with an average length of body of 23 inches, has also 5g inches. L. glacialis, found in common with the American, 7 lb. weight, and 22*6 inches long, has dimensions as follows :-from wrist-joint to end of claw 2 inches 9 lines, heel to point of middle claw 5 inches 9 lines. Not only is the foot of L. americanus proportionately lengthened, but a remarkable degree of lateral extension is allowed between the metacarpal and metatarsal bones, with great laxity of the web membrane. Inhabiting the woody districts, where the snow remains deep and soft during the greater part of the winter, the advantage of such a modification in the feet, especially when combined with the lengthened stiff' winter hair on the treading-surface, is apparent, allowing it to pass over the softest snow with tbe slightest impress, and thus giving it the power of eluding by swiftness its numerous enemies. A recent impress of these natural snow-shoes gave the following shape and dimensions:-Fore feet oval, each 3| inches long by 2 inches broad. Hind feet egg-shaped (large end anteriorly), each 6 inches long by 3 inches in front and 1| inch behind. The average snow-shoes adapted to an ordinary-sized man have a superficial area 5| inches for each pound in weight, which is extended in this Rodent to 11*4 inches. In the Hudson's Bay Territory L. glacialis and L. americanus exist in the same district, the one inhabiting the open barrens, the other the soft snowy woodlands. It appears much to be desired that the modifications in the feet and winter coat of this Rodent, under different latitudes and variations of natural conditions, should be accurately traced out, inasmuch as the indications are that, both in the one and the other, they fully illustrate the capability of external circumstances to call forth structural changes, placing the animal frame in harmony with the surrounding natural features, and allowing it to compete advantageously with its numerous and powerful enemies in the great struggle for existence. 3. Notes on the Habits of the Collared Plain Wanderer (Pedionomus torquatus, Gould). By W . V I N C E N T L E G G E, F.Z.S. Mr. Gould says this bird is not uncommon in South Australia, where it inhabits the plains of the interior; but I think he does not record its presence in Victoria. It makes its appearance in |