Shell nut-shaped, tuberculate, with distinct sagittal stricture. On each side of the ring four pairs of larger annular pores. Lateral pores roundish, smaller. Basal plate with four large central and a circle of eight to twelve smaller peripheral pores. Horn cylindrical, about half as long as the shell (in the inverted figure of Ehrenberg directed downwards).
Dimensions.—Shell 0.1 to 0.15 long, 0.15 to 0.2 broad; horn 0.05 to 0.08 long.
Habitat.—Fossil in Barbados.
3. Circospyris tridentata, Haeckel.
Dictyospyris tridentata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xix. fig. 10, a, b.
Shell nut-shaped, smooth, with sharp sagittal stricture. On each side of the ring two pairs of large annular pores. Lateral pores roundish, smaller. Basal plate with six large pores. Horn slender, cylindrical, about as long as the shell, with three sharp teeth at the distal end.
Dimensions.—Shell 0.03 long, 0.05 broad; horn 0.03 long.
Habitat.—Fossil in Barbados.
Genus 468. Dictyospyris,[[86]] Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 54.
Definition.—Zygospyrida without basal feet, and without coryphal horns.