_Habitat._--Central Pacific, Station 266, depth 2750 fathoms. Genus 455. _Cantharospyris_,[73] n. gen. _Definition._--#Zygospyrida# with six basal feet, without apical horn. The genus _Cantharospyris_ differs from the preceding two hexapodal genera in the absence of horns on the coryphal face, and has therefore the same relation to them that the hornless _Tristylospyris_ bears to the one-horned _Tripospyris_ and the three-horned _Triceraspyris._ {1051}1. _Cantharospyris carabus_, n. sp. Shell nut-shaped, with deep sagittal stricture and irregular roundish pores. Basal plate with six larger pores. Six feet of different sizes, cylindrical, curved; three primary feet (one caudal and two pectoral) about as long as the shell and twice as long as the three secondary feet. _Dimensions._--Shell 0.08 long, 0.12 broad; feet 0.05 to 0.09 long. _Habitat._--Tropical Atlantic, Station 338, depth 1990 fathoms; Central Pacific, Station 268, depth 2900 fathoms. 2. _Cantharospyris ateuchus_, Haeckel. _Ceratospyris ateuchus_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xxi. fig. 4. Shell nut-shaped, tuberculate, with slight sagittal stricture and unequal circular pores. Basal plate with six larger pores. The two pectoral feet very large and stout, four to six times as long as the shell, widely divergent, curved. The four other feet much smaller and thinner, about as long as the shell. _Dimensions._--Shell 0.06 long, 0.08 broad; length of the two larger feet 0.2 to 0.3, of the four smaller 0.05 to 0.07. _Habitat._--Fossil in Barbados. 3. _Cantharospyris radicata_, Haeckel. _Ceratospyris radicata_, Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 43; Mikrogeol., 1854, Taf. xxii. fig. 37. _Haliomma radicatum_, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 83. _Petalospyris radicata_, Haeckel, 1862, Monogr. d. Radiol., p. 295. _Petalospyris radicata_, Stöhr, 1880, Palæontogr., vol xxvi. p. 79, Taf. iii. fig. 11. Shell nut-shaped, smooth, with slight sagittal stricture and irregular roundish pores; two larger pores on each side of the ring. Basal plate with six pores (?). Six feet of equal size and similar form, conical, divergent, slightly curved, shorter than half the ring. _Dimensions._--Shell 0.05 long, 0.08 broad; feet 0.02 long. _Habitat._--Fossil in Barbados and Sicily. 4. _Cantharospyris platybursa_, n. sp. (Pl. 53, fig. 7). _Platybursa compressa_, Haeckel, 1881, Prodromus, p. 429; Atlas, pl. 53, fig. 7.