Shell nearly cubical, smooth, with slight sagittal stricture. Pores roundish; three pairs of larger pores on each side of the ring. Basal plate with six large pores. Five feet of equal length, slender, spindle-shaped, about as long as the shell, divergent. Apical horn conical, and half as long as the feet. _Dimensions._--Shell 0.08 long, 0.09 broad; horn 0.05 long, feet 0.1 long. _Habitat._--Fossil in Barbados. Genus 457. _Aegospyris_,[75] Haeckel, 1881, Prodromus, p. 442. _Definition._--#Zygospyrida# with five basal feet and three coryphal horns. The genus _Aegospyris_ differs from the preceding _Clathrospyris_, its ancestral form, in the possession of three horns on the coryphal face (one odd apical, and two paired frontal horns on each side), and therefore bears to the latter the same relation that _Triceraspyris_ does to _Tripospyris_, and _Liriospyris_ to _Hexaspyris_. 1. _Aegospyris aequispina_, n. sp. Shell nut-shaped, tuberculate, with slight sagittal stricture. Pores subregular circular. Basal plate with four large collar pores. Three horns and five feet all of equal size and similar form, slender conical, slightly curved, widely divergent, about as long as the shell. _Dimensions._--Shell 0.08 long, 0.11 broad; horns and feet 0.08 long. _Habitat._--Central Pacific, Stations 265 to 274, depth 2350 to 2925 fathoms. 2. _Aegospyris octospina_, n. sp. Shell nearly cubical, smooth, with slight sagittal stricture. Pores subregular circular; two pairs of larger pores on each side of the ring. Basal plate with four large pores. Two paired horns and four paired feet of equal size and similar form, S-shaped curved, twice as long as the shell. Odd horn and odd feet half as long, straight, conical. _Dimensions._--Shell 0.08 long, 0.09 broad; six paired spines 0.2 long, two odd spines 0.1 long. _Habitat._--South Atlantic, Station 323, depth 1900 fathoms. {1054}3. _Aegospyris longibarba_, Haeckel. _Ceratospyris longibarba_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xxi. figs. 1, 2. Shell nut-shaped, tuberculate, with slight sagittal stricture. Pores subregular circular. Basal plate with four larger central, and eight smaller peripheral pores. Apical horn and caudal foot short, straight, conical; two frontal horns longer, curved; four paired feet slender, curved, twice as long as the shell. _Dimensions._--Shell 0.06 long, 0.08 broad; paired horns 0.03 long, paired feet 0.1 long. _Habitat._--Fossil in Barbados. 4. _Aegospyris aegoceras_, n. sp. (Pl. 95, fig. 10). Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores irregular roundish. Basal plate with three large pores. Apical horn and caudal foot short, straight, spindle-shaped; two frontal horns as long as the shell, strongly curved; four paired feet also curved, at the distal end forked, divergent; the tergal thinner and as long as the shell, the pectoral thicker and twice as long.