This natural order is one of singular interest. The majority of the species are herbaceous, but some form considerable stems, both thick and long, of perennial duration, yet of herbaceous texture; and in the moist, shady forests of the tropics certain species of the genus Philodendron and other allied genera climb a great height on the trees by means of their long aerial roots. The flowers of the Aroids are destitute of beauty from a floricultural point of view. They are rarely, in fact, visible, being usually included and concealed within the bract, or spathe, as it is technically called, which in one form or another accompanies and is characteristic of the inflorescence of the order. But even when visible, the individual flowers are far from being imposing; stamens and pistils are the only organs produced, and they are crowded together promiscuously or separately on the sides of the club-like or spike-like body which occupies the centre of the spathe, and is called the spadix. The spathe, however, is in some cases a very beautiful and conspicuous object in the inflorescence of Aroideae - so beautiful, indeed, as quite to compensate for the deficiency of the flowers in that respect.

Calla (Richardia) aethiopica may be pointed to as a well-known and charming example of the ornamental character of the spathe in some Aroids. In this case it rivals driven snow in its pure white colour, while its elegant form and the beautiful yellow spadix present a combination of charms scarcely surpassed in subjects having a higher development of strictly floral organs. The members of the group are more remarkable, however, for the beauty or singularity of their leaves than for any beauty they are possessed of in regard to inflorescence. The picturesque Caladiums, the lattice-leaved Philodendrons, and the hard, rigid leaves of certain species of Anthurium, suggesting, as they do, the idea that they are cast in bronze, or have at some period of their existence undergone a process of petrifaction and yet retained life, excite mingled feelings of wonder and admiration in the mind. The group, in the main, has a strange old-world or pre-Adamite aspect about it, which is fascinating in an intense degree.

Certain species vaguely associate themselves in the mind with the terrestrial and atmospheric conditions of some bygone epoch, when earth-heat was greater than it now is, and the atmosphere a vapour-bath; when, according to the evolutionists, man was yet - we dare hardly guess what or where - without a dream of either descent or destiny perhaps had not even assumed a tail or aspired to living in trees. The greater bulk of the order inhabits the warmer regions of the world, and cannot, therefore, be made available for out-of-doors gardening in this country. Some, however, are found in the temperate and northern latitudes, and amongst these we shall find a few subjects worthy of culture for one purpose or another in our gardens.