The Cortiniscida, the second subfamily of Semantida, differ from the preceding Semantiscida in the possession of three typical basal feet, which are probably inherited from the Cortinida, and perhaps indirectly from the Plagonida (_Plagoniscus_). The simplest and the most important form of this second family is _Cortiniscus_ (Pl. 92, figs. 11-13), differing from its probable ancestral form, _Cortina_, in the development of a basal ring, produced by horizontal union of the basal apophyses. The three typical feet are the same as in all triradiate NASSELLARIA, two paired pectoral feet (_p__{1}, _p__{11}) diverging on the anterior base of the sagittal ring, whilst the odd caudal foot (_c_) lies on its posterior base in the sagittal plane and appears as a basal prolongation of the dorsal rod of the sagittal ring; the upper part of the dorsal rod is usually prolonged into an ascending apical horn. In _Stephaniscus_ (Pl. 92, figs. 14, 15) four basal feet are visible, an anterior or sternal foot (_z_) being added as a prolongation of the basal rod of the ring, opposite to the caudal foot. Finally, _Semantiscus_ (Pl. 92, figs. 16-18) is distinguished by the possession of six divergent basal feet, probably identical with those of all six-radiate NASSELLARIA; three of these may be regarded as primary and perradial, the odd caudal and the paired pectoral feet; the three other intercalated as secondary or interradial feet, the odd sternal (_z_) and the paired tergal feet (_t__{1}, _t__{11}).