One of perhaps the most deeply interesting departments of your great British Museum--the wonder of the world--is that noble gallery, consisting of a suite of rooms, opening in line, the one beyond the other, which forms its rich storehouse of organic remains. You must of coarse remember the order in which the organisms of that gallery are ranged. The visitor is first ushered into a spacious room devoted to fossil plants, chiefly of the Coal Measures. And if these organisms are in any degree less imposing in their aspect than those of the apartments which follow in the series, it is only because that, from the exceeding greatness of the Coal Measure plants, they can be exhibited in but bits and fragments. Within less than an hour's walk of the Scottish capital there are single trees of this ancient period deeply embedded in the sandstone strata, which, though existing as mere mutilated portions of their former selves, would yet fail to find accommodation in that great apartment. One of those fossil trees,--a noble araucarian,--which occurs in what is known as the Granton quarry, is a mere fragment, for it wants both root and top, and yet what remains is sixty-one feet in length by six feet in diameter; and beside it there lies a smaller araucarian, also mutilated, for it wants top and branches, and _it_ measures seventy feet in length by four feet in diameter. I saw lately, in a quarry of the Coal Measures about two miles from my dwelling-house, near Edinburgh, the stem of a plant (_Lepidodendron Sternbergii_), allied to the dwarfish club mosses of our moors, considerably thicker than the body of a man, and which, reckoning on the ordinary proportions of the plant, must have been at least seventy feet in height. And of a kind of aquatic reed (calamites), that more resembles the diminutive mare's tail of our marshes than aught else that now lives, remains have been found in abundance in the same coal field, more than a foot in diameter by thirty feet in length. Imposing, then, as are the vegetable remains of this portion of the National Museum, they would be greatly more imposing still did they more adequately represent the gigantic flora of the remote age to which they belong. [Illustration: Fig. 91. CALAMITES CANNÆFORMIS.]