If you are in doubt as to whether a hypanthium is present, turn the flower upside down and look at where the pedicel ends. Leaves of different groups have a somewhat different structures. Some of the differences are anatomical. Compare, for instance, the cross-section of a pine needle with that of a grass or maple. Others are morphological and easily seen.
Some leaves have stipules at the base of the petiole.
Leaves with a single blade are said to be simple . In compound leaves , there are several leaflets , i.e., distinct parts of the blade. Most grasses have a ligule at the junction of the leaf sheath and leaf blade. In some grasses it consists of hairs. The Selaginellales and Isoetales have a small ligule in the leaf axils.