Partiform

The term for a gonyaulacalean hyposomal tabulation pattern in which the posterior sulcal plate (Z) is usually distinctly omegaform, consistently within the sulcus, and extends further to the anterior than does the posterior intercalary plate (X). The large size of the posterior sulcal plate and its anteriorward extension is reciprocated by the small size of the right sulcal plate (Ii) and the left sulcal plate (Im). See also quinqueform and sexiform. Refer to Text-Figure 64A.