Stems: slender, from a branching rootstock, minutely pubescent. Leaves; linear-oblanceolate. Flowers: few, on pedicels; calyx inflated, with short obtuse teeth; petals little exserted, with a broadly-auricled claw, and large, thin quadrate appendages, the flabellate bifid blade with a linear tooth on each side.

Like many of the Campions, this one is very sticky, and is characterized, in common with other members of the Pink Family, by its slender stems being jointed and the leaves set in pairs at the joints. It gives out a faint sweet odour, and is usually found growing among the stones on steep hillsides.

Silene Lyallix, or Lyall's Catchfly, has spoon-shaped basal leaves and long narrow stem leaves. The white flowers grow on short stalks in loose terminal heads; the inflated calyx has purple-tipped teeth and the petals are spreading and two-lobed. The flowers are sometimes purplish.