In the example selected for our plate the pinnules are oblong, obtuse and crenulate, or at most, crenately-toothed.
The margin was entire, and not crenulate, as in many dolphins.
In some other plants the edges are serrulate, crenulate, etc.
crenulate: with small scallops, evenly rounded and rather deeply curved.
Processes large near the ends of the major axis and not oblique to it, or scarcely so, the edges with a crenulate border.
Petals (crenulate) and stamens 5, inserted on the margin of a cup-shaped disk which lines the base of the calyx.
Crenulata means bearing notches, referring to the crenulate form of the gills, which are very distinct.