The black poplars are so much like the aspen as to be easily mistaken, especially as their leaves rustle in the same way. But the true aspen has a smooth bark, while that of the black poplar is scored or rough. Woodmen always call the aspen the 'asp,' dropping the termination. In the spring the young foliage of the black poplar has a yellow tint. When they cut down the alder poles by the water and peeled them, the sap under the bark as it dried turned as red as if stained. The paths in spring were strewn with the sheaths of the young leaves and buds pushing forth; showers of such brown sheaths came off the hawthorn with every breeze. These, with the catkins, form the first fall from tree and bush. The second is the flower, as the May, and the horse-chestnut bloom, whose petals cover the ground. The third fall is that of the leaf, and the fourth the fruit. On the Scotch fir the young green cones are formed about the beginning of June, and then the catkin adjacent to the cone is completely covered with quantities of pale yellow farina. If handled, it covers the fingers as though they had been dipped in sulphur-flour; shake the branch and it flies off, a little cloud of powdery particles. The scaly bark takes a ruddy tinge, when the sunshine falls upon it, and would then, I think, be worthy the attention of an artist as much as the birch bark, whose peculiar mingling of silvery white, orange, and brown, painters so often endeavour to represent on canvas. There is something in the Scotch fir, crowned at the top like a palm with its dark foliage, which, in a way I cannot express or indeed analyse, suggests to my mind the far-away old world of the geologists. In the boughs of the birch a mass of twigs sometimes grows so close and entangled together as to appear like a large nest from a distance when the leaves are off. Even as early as December the tomtits attack the buds, then in their sheaths, of the birch, clinging to the very extremities of the slender boughs. I once found a young birch growing on the ledge of a brick bridge, outside the parapet, and some forty or fifty feet from the ground. It was about four feet high, quite a sapling, and apparently flourishing, though where the roots could find soil it was difficult to discover.