| 1 | Leaves distinctly auricled at the base (auricles sometimes obscure on leaves of young twigs or sapling on C. auriculatum; sometimes obscure or wanting on leaves of young or fertile twigs in C. brevipetio-latum). Fruits 6-8 mm long. |
| 1' | Leaves not auricled (except forming amplexicaul auricles on sapling leaves in C. squamatum; sometimes (obscurely) auriculate on vegetative leaves in C. montanum). Fruits 11-18 mm long. |
| 2 | Leaf-base gradually, narrowly decurrent, the lower very narrowly winged part petiolar between the proper blade and the auricles (Fig. 59j). Fruits in transverse section showing a solid septum |
| 2' | Leaf-base gradually, broadly decurrent, without such narrowly winged petiole (Fig. 59l). Fruits in transverse section showing a hollow septum |
| 3 | Leaf-base distinctly set off against a distinct petiole 2-8 cm long (Fig. 59a). Fruits in transverse section showing a hollow septum |
| 3' | Leaf-base either gradually tapering towards the insertion or petiole up to ¾ cm. |
| 4 | Leaf-base broad, petiole up to ¾ cm (Fig. 59i). Calyx lobed to ½ of its length. Fruits in transverse section showing a hollow septum |
| 4' | Leaf-base gradually tapering to the base (Fig. 59h). Calyx lobed almost to the base. Fruits in transverse section showing a solid septum |
