Habitat.—Mediterranean (Messina), Haeckel.
14. Stylodictya echinastrum, Ehrenberg.
Stylodictya echinastrum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 84, Taf. xxiii. fig. 1.
All rings of the disk convoluted in a double spiral, of nearly equal breadth. Pores irregular, roundish, two to three on the breadth of each ring. Marginal spines numerous, twenty to thirty, of very different size, the largest conical, strong, about as long as the diameter of the disk, and on the base as broad as one ring.
Dimensions.—Diameter of the disk (with five rings) 0.12; breadth of each ring 0.01; pores 0.002 to 0.006.
Habitat.—Fossil in the rocks of Barbados.
15. Stylodictya clavata, Ehrenberg.
Stylodictya clavata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 84, Taf. xxiii. fig. 2.
All rings of the disk convoluted in a half spiral, of nearly equal breadth; each ring by four zigzag beams (crossed in two perpendicular diameters) divided into four equal quarters; the spiral line of each quarter ring halving both neighbouring quarters. Pores regular, circular, two on the breadth of each ring. Eight marginal spines short, conical, with thin pedicle; four perradial (as prolongations of the four internal beams) alternating with four interradial spines arising from the margin of the disk.
Dimensions.—Diameter of the disk (with five rings) 0.13; breadth of each ring 0.014; pores 0.003.