Sagittal ring ovate, thorny, with three distorted edges; dorsal rod nearly straight and vertical prolonged upwards into a stout thorny apical horn, downwards into the caudal foot. Basal ring smaller than the sagittal ring, with four elliptical or nearly triangular gates; the two anterior (jugular pores) about half as large as the two posterior (cardinal pores). Three feet of equal size, thorny, divergent, straight or slightly curved, about as long as the diameter of the sagittal ring. _Dimensions._--Height of the sagittal ring 0.14 to 0.18, breadth 0.1 to 0.12. _Habitat._--Cosmopolitan; Atlantic, Indian, Pacific, at various depths. {965}Genus 412. _Stephaniscus_,[31] n. gen. _Definition._--#Semantida# with four typical basal feet (two sagittal and two lateral or pectoral feet). The genus _Stephaniscus_ differs from the preceding _Cortiniscus_ in the production of a fourth (sternal) foot, and therefore exhibits the same relation to it that _Stephanium_ among the Stephanida bears to _Cortina_. It differs from _Stephanium_, in the production of a basal ring, with pores or gates between the bases of the basal feet. Two of these feet are sagittal (the posterior caudal and the anterior sternal foot), whilst the other two are lateral or pectoral (right and left). The basal lattice-plate exhibits either two pores ("jugular gates") or four pores (two anterior jugular and two posterior cardinal gates). 1. _Stephaniscus tetrapodius_, n. sp. Sagittal ring nearly circular, smooth, with a short conical apical horn. Basal ring square, smooth, with two triangular gates. Four feet simple, equal, conical, divergent, about as long as the diameter of the ring. _Dimensions._--Height of the sagittal ring 0.08, breadth 0.07. _Habitat._--Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms. 2. _Stephaniscus quadrifurcus_, n. sp. (Pl. 92, fig. 14). Sagittal ring subcircular, thorny with a small thorny apical horn. Basal ring also nearly circular, with two large semicircular gates and a few small thorns. All four feet curved and forked, the fork-branches again ramified, with numerous short curved and pointed branches. The two lateral feet (right and left) are larger and more branched than the two sagittal feet (sternal and caudal foot). _Dimensions._--Height of the sagittal ring 0.12, breadth 0.1. _Habitat._--Central Pacific, Station 266, depth 2750 fathoms. 3. _Stephaniscus quadrigatus_, n. sp. (Pl. 92, fig. 15).