The genus _Stephanium_ differs from the preceding nearly allied _Cortina_ in the production of four basal feet; the new foot, missing in the latter, is the anterior or sternal foot. Therefore _Stephanium_ may be regarded as the archetype of all those NASSELLARIA in which, on the base of the sagittal ring, there are developed four typical feet--two sagittal feet (the posterior caudal and anterior sternal foot) and two lateral feet (right and left). On the origin of _Stephanium_ compare above, p. 893, &c. 1. _Stephanium quadrupes_, n. sp. (Pl. 92, fig. 20). Ring ovate, with three prominent dentate edges and a short pyramidal apical horn. Four feet all of nearly equal size, about as long as the ring, also with three thorny edges, in the upper half divergent, in the lower convergent. _Dimensions._--Height of the ring 0.12, breadth 0.08; length of the feet 0.11 to 0.13. _Habitat._--Central Pacific, Station 266, depth 2750 fathoms. 2. _Stephanium tetrapus_, n. sp. Ring elliptical, without edges, thorny, with a stout, thorny apical horn of the same length. Four feet curved and irregularly branched, divergent, of different size. The two sagittal feet (the anterior sternal and posterior caudal) about as long as the ring. The two lateral feet (right and left) nearly twice as long, more richly branched. _Dimensions._--Height of the ring 0.16, breadth 0.11; length of the feet 0.15 to 0.3. _Habitat._--Central Pacific, Station 272, depth 2600 fathoms. Fossil in Barbados. {953}Family XLIX. #SEMANTIDA#, n. fam. _Definition._--#Stephoidea# with a single vertical ring (the primary sagittal ring), bearing on its base a horizontal ring (basal or cortinar ring) with two to four or more basal gates (or cortinar pores). The family #Semantida# differs from the preceding Stephanida in the development of a small horizontal ring on the base of the primary vertical sagittal ring. By the crossing of these two rings a small latticed basal plate is formed, with one or two pairs of pores; rarely with a greater number of "basal pores." The production of this characteristic "basal plate" is of the greatest morphological importance, as the beginning of the numerous different lattice-formations, which are differentiated in the great majority of NASSELLARIA.