 In some other plant groups, such as the speedwell genus "Veronica", petiolate and sessile leaves may occur in different species.In the grasses (Poaceae) the leaves are apetiolate, but the leaf blade may be narrowed at the junction with the leaf sheath to form a "pseudopetiole", as in "Pseudosasa japonica".In plants with compound leaves, the leaflets are attached to a continuation of the petiole called the rachis.