Subgenus 3. Podocyrtidium, Haeckel.
Definition.—Feet convergent (the distance between their ends being smaller than that between their bases). Pores of the thorax and abdomen nearly equal in size and similar in form.
26. Podocyrtis papalis, Ehrenberg.
Podocyrtis papalis, Ehrenberg, Mikrogeol., Taf. xxxvi. fig. 23; Abhandl. d. k. Akad. d. Wiss. Berlin, 1875, p. 82, Taf. xv. fig. 6.
Shell ovate, smooth, without external stricture. Length of the three joints = 1 : 3 : 1, breadth = 1 : 3 : 3. Cephalis ovate, with a stout pyramidal horn of twice the length. Thorax and abdomen with about thirty longitudinal, divergent ribs, separating the same number of longitudinal rows of regular, circular pores, the size of which increases gradually towards the base. Feet shovel-shaped (broad, triangular, with convex outer and concave inner side, the obtuse end being curved inwards), about as long as the short abdomen, only slightly convergent.
Dimensions.—Length of the three joints, a 0.04, b 0.12, c 0.04; breadth, a 0.04, b 0.12, c 0.11.
Habitat.—Fossil in Barbados.
27. Podocyrtis costata, n. sp.
Shell ovate, smooth, of the same form and structure as Podocyrtis papalis, but with two distinct strictures and different proportions. Length of the three joints = 1 : 3 : 6, breadth = 2 : 4 : 6. About thirty longitudinal ribs regularly alternating with rows of circular, regular pores. Feet as in Podocyrtis papalis.
Dimensions.—Length of the three joints, a 0.02, b 0.06, c 0.12; breadth, a 0.04, b 0.08, c 0.12.