Note 10 — Chapter XII · SOME ANOMALIES

These are not casual variations, differing from flower to flower; all the roses present the same arrangement, all have their sepals divided into three classes in the matter of beards. It is a fixed rule, resulting from a law which governs floral architecture, even as the art of a Vitruvius10 governs our buildings. This law, so elegant in its simplicity, is thus stated in botany: in the quinary order, the most important order of the vegetable world, the flower groups the five portions of a whorl at intervals upon a close spiral, almost equivalent to the circumference of a circle; and this arrangement is so contrived that two turns of the spiral contain the series of five parts.