Cotyledons can be divided into two groups. Group one consists of evergreen plants with a summer growing period. Group two is made up of deciduous plants, with large, solid fleshy stems. This group grows during the winter, and sheds its leaves during the summer. The plants hang in dangling mats or curtains of 60 cm long branched stems from sheer south-facing cliffs. Flowers grow in small clusters of up to four at a stem tip. The bell-shaped flowers petal lobes curl back, exposing the anthers.