Basal ring and frontal ring nearly circular, without sagittal constriction. Sagittal ring elliptical, prolonged at the apex into an apical horn from which two branched lateral bows descend and unite with the uppermost parts of the frontal ring. Four other small bows descend from the lowermost parts of the latter and unite with the basal ring. From the lateral corners of the basal ring descend two short vertical feet. (May be regarded as derived from _Podocoronis toxarium_, Pl. 83, Fig. 7, by development of the bows connecting the rings.) _Dimensions._--Height of the frontal ring 0.11, breadth 0.13. _Habitat._--Central Pacific, Station 265, depth 2900 fathoms. 3. _Plectocoronis pentacantha_, n. sp. (Pl. 93, fig. 6). Basal ring and frontal ring kidney-shaped, with deep sagittal constriction. Sagittal ring ovate, prolonged at the apex into an oblique horn. From the edges of the angular rings delicate threads arise, which anastomose and form irregular arachnoidal meshes, partly closing the four open lateral gates. Two basal gates simple. From the four nodal points of the basal ring there arise four, short diverging feet, comparable to rudimentary cortinar feet (two lateral from the frontal ring and two sagittal from the primary ring, as basal prolongations). _Dimensions._--Height of the frontal ring 0.12, breadth 0.18. _Habitat._--Central Pacific, Station 271, surface. {980}Genus 420. _Podocoronis_,[39] Haeckel, 1881, Prodromus, p. 445. _Definition._--#Coronida# with six large gates (four lateral and two basal). Skeleton composed of two complete rings (the sagittal and basal) and one incomplete (frontal) ring. Basal ring provided with typical, regularly disposed, descending feet (cortinar feet). The genus _Podocoronis_ differs from the two preceding nearly allied genera in the development of typical radial feet on the basal ring, which by their regular disposition and their general appearance among the #Spyroidea# and #Cyrtoidea# obtain great morphological importance. According to the different number and disposition of these basal feet (or "cortinar feet"), the following subgenera may be distinguished (regarded in my Prodromus, 1881, p. 445, as separate genera):--_Dipocoronis_ with two lateral feet, _Tripocoronis_ with three cortinar feet (most important!), _Tetracoronis_ with four crossed feet, _Hexacoronis_ with six radial feet, _Stylocoronis_ with numerous (8 or more feet). These subgenera have important relations to the corresponding genera of Zygospyrida. Subgenus 1. _Dipocoronis_, Haeckel, 1881, Prodromus, p. 445. _Definition._--Basal ring with two descending lateral feet (right and left) as prolongations of the frontal ring. 1. _Podocoronis dipodiscus_, n. sp.