Table 3.1 summarizes the symbols for the floral diagrams used in this book. When constructing floral diagrams it is essential to orientate the flowers correctly (Fig. 3.1). Arrangement of individual organs and their orientation can only be accurately compared if a common reference point is being used. The main axis relative to the flower is shown by a black dot. The main axis of the inflorescence is shown by a crossed circle. Flowers are conventionally depicted with the axis on top and the main subtending bract below along the median line. Bracteoles are placed more or less in transversal position depending on their orientation relative to the main axis. To differentiate bracts and bracteoles from the perianth, a small triangle is placed on the abaxial side of the bract(eole). A bract or bracteole that is lost or early deciduous is shown in white with a broken outline. A large straight arrow represents the main direction of monosymmetry, when present. If flowers are resupinate, this is shown by a curved arrow.

The distinction between sepals, petals and tepals is based on the presence versus absence of petaloidy, as the differentiation between sepals and petals is sometimes unclear (see p. 6). White curves represent pigmented (petaloid) organs, without distinction between sepals, petals or tepals, as these represent homologous organs in most cases (cf. Ronse De Craene, 2007, 2008).