[79] Ulmus americana and ulmus alata.--JAMES. [80] _Maclura Aurantiaca_, NUTTALL.--A description of this interesting tree may be seen in Mr. Nuttall's valuable work on the Genera of North American Plants, vol. ii. p. 233. That description was drawn from specimens cultivated in the garden of Mr. Choteau, at St. Louis, where, as might be expected, the tree did not attain its full size and perfect character. In its native wilds, the Maclura is conspicuous by its showy fruit, in size and external appearance resembling the largest oranges. The leaves are of an oval form, with an undivided margin, and the upper surface of a smooth shining green; they are five or six inches long, and from two to three wide. The wood is of a yellowish colour, uncommonly fine and elastic, affording the material most used for bows by all the savages from the Mississippi to the Rocky Mountains. How far towards the north its use extends we have not been informed; but we have often seen it among the lower tribes of the Missouri, who procure it in trade from the Osages and the Pawnees of Red river. The bark, fruit, &c. when cut into, exude a copious, milky sap, which soon dries on exposure, and is insoluble in water; containing, probably, like the milky pieces of many other of the urticæ, a large intermixture of caotchouc, or gum elastic. Observing this property in the milky juice of the fruit, we were tempted to apply it to our skin, where it formed a thin and flexible varnish, affording us, as we thought, some protection from the ticks. The fruit consists of radiating, somewhat woody fibres, terminating in a tuberculated and slightly papillose surface. In this fibrous mass the seeds, which are nearly as large as those of a quince, are disseminated. We cannot pretend to say what part of the fruit has been described as the "pulp which is nearly as succulent as that of an orange; sweetish, and perhaps agreeable when fully ripe." In our opinion, the whole of it is as disagreeable to the taste, and as unfit to be eaten as the fruit of the sycamore, to which it has almost as much resemblance as to the orange. The tree rises to the height of twenty-five or thirty feet, dividing near the ground into a number of long, slender, and flexuous branches. It inhabits deep and fertile soils along the river valley. The Arkansa appears to be the northern limit of the range of the maclura, and neither on that river, nor on the Canadian, does the tree or the fruit attain so considerable a size as in warmer latitudes. Of many specimens of the fruit examined by Major Long, at the time of his visit to Red river, in 1817, several were found measuring five and an half inches in diameter.--JAMES. [81] Pike was the first to describe as a desert the fine grazing lands of the Great Plains; Long and Pike agreed in thinking them providentially placed to keep the American people from ruinous diffusion. The myth of the Great American Desert lived for half a century.--ED.