Basal breadth of all six the same (three times as large as one pore); form, three-sided prismatic, with cuspidate distal end.
Cuspidate, tipped with a sharp and rigid point; as in Fig. 140.
The serrations tend to be more nearly crenulate than cuspidate.
Leaves much smaller, less oblique at the base, finely and regularly crenate, acuminate rather than cuspidate.