This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
The peculiarity of this genus is the rayed flower-heads, the ray-florets being female, and the disk-florets male. Only one species comes within our province. The generic name is derived from the Latin calendae, in allusion to the constant flowering of the common species.
1. C. Officinalis. Common Marigold. - This familiar annual is a native of the South of Europe. Like many other Composites it has undergone considerable modification in the florets, forming the double flower (fig. 147) of florists. The bright orange flowers are very showy, in the latter variety particularly so.
Fig. 147. Calendula officinalis flore pleno, (1/4 nat. size.)