Fig. 7.2-8. Longitudinal section of vessel element of corn (Zea mays). Corn is a flowering plant (as opposed to a conifer), so its circular bordered pits are small, like those of American hornbeam in Fig. 7.2-7, rather than large like those of pine in Fig. 7.2-6. Notice that these circular bordered pits are not quite as orderly as the ones in American hornbeam; they are of various sizes, some quite a bit larger than others, and they do not form a neat hexagonal arrangement. The regularity of pitting is variable – in some species, scalariform pits or circular bordered pits are remarkably regular; in others, they are almost haphazard.