Despite all the improvements and inventions of modern times, classic architecture has made no progress since the days of Pericles. All that we do now is but to reproduce what the Greeks created 2000 years ago, and he is reckoned the best architect who furnishes the best imitation. Our architects might find some useful hints, however, by studying the lowlier orders of nature. They would see there patterns of beauty far more delicate than the Grecian capital, and more light and airy than the Gothic shaft. And whether or not they could found a new order of architecture, they could not fail to discover many modifications and improvements upon some of the old. They could not readily light upon a more graceful form than that of the lithostrotion, would they but picture it as it grew at the bottom of the old carboniferous sea. A group of hexagonal pillars, firmly compacted together like those of the Giant's Causeway, or Fingal's Cave, rose from a white calcareous pediment, as columns from the marble steps of an Athenian temple. Each side of the pillar had a wavy undulating surface, delicately fluted by long slender striæ, the whole being so arranged that the convexities of one surface fitted into the sinuosities of the adhering one. Each pillar was crowned above by a capital, consisting of the soft vibratile tentacles of the animal, that hung over like so many acanthus leaves. Of the form of these tentacles, their design and grouping, we know nothing save what may be gathered from the analogy of living corals. There can be little doubt, however, that, like the flower-shaped buds of the existing reef-building polyps, they must have been eminently beautiful, and in strict keeping with the graceful column which they crowned. Another kindred form was that known as the _lithodendron_. It, too, grew in colonies, and seems to have closely resembled the last, save that the pillars, in place of being six-sided, were round. I have seen a bed of these corals several yards in extent, and seven or eight inches deep, where the individuals were closely crowded together, so as to resemble a series of tobacco-pipe stems, or slim pencils set on end. The tubes, however, were not all quite straight; many being more or less curved, and sometimes crossing their neighbours obliquely. The internal arrangement was on the same plan as in the two previous corals. The same numerous partitions ran from the exterior wall towards the central tube, the same thick-set diaphragms crossed the entire breadth of the column, imparting the same minute honey-combed appearance to a cross section. The exterior of the column (in _L. fasciculatum_) was likewise traversed by the same longitudinal striæ.