The leaves of fern show circinate, vernation (circinate ptyxis) ie, the leaves of fern in young stage are tightly rolled but uncoil like a watch spring. The growing point come to lie in the centre. The leaves in moss are flat, simple, thin, more or less sessile with a well defined midrib. These do not show circinate vernation. In algae the plant body is not differentiated into root, stem and leaf. Therefore, the circinate vernation is absent. Two types of leaves are found in gymnosperms (Cycas, Pirtus). The circinate vernation is absent (except Cycas).