Chapter VIII: Front Matter (8)

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.

Shell smooth, nearly discoidal circular, markedly compressed in the sagittal direction, with slight basal stricture. Pores very numerous, irregular polygonal, with thin bars. Basal plate with four very large pores. Six feet short, conical, nearly horizontally expanded. Two sagittal feet (caudal {1052}and sternal) larger, about half as long as the shell (shortened in the figure). The two sternal feet larger than the two small or rudimentary tergal feet.

_Dimensions._--Shell 0.15 long, 0.13 broad; feet 0.02 to 0.06 long.

_Habitat._--Central Pacific, Station 271, depth 2425 fathoms.

Subfamily 5. PENTASPYRIDA, Haeckel, 1881, Prodromus, p. 442.

_Definition._--#Zygospyrida# pentapoda, with five descending basal feet, one odd caudal foot, and two pairs of lateral feet (two anterior or pectoral, and two posterior or tergal feet).

Genus 456. _Clathrospyris_,[74] Haeckel, 1881, Prodromus, p. 442.

_Definition._--#Zygospyrida# with five basal feet and one apical horn.

The genus _Clathrospyris_ and the two following closely allied genera represent together the small subfamily of Pentaspyrida, differing from the other Zygospyrida in the possession of five descending feet on the basal face. Three of these are the primary cortinar feet (of _Cortiniscus_, _Plagoniscus_, _Tripospyris_, &c.), whilst the two others are secondary tergal feet. The Pentaspyrida may therefore be probably derived from the Hexaspyrida by loss of the odd anterior or sternal foot.

1. _Clathrospyris camelopardalis_, n. sp.

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores irregular roundish. Basal plate with six pores (?). Two pectoral feet very large, twice as long as the shell, cylindrical, curved. Two tergal feet half as long and thick as the pectoral. Caudal foot and apical horn straight, conical, half as long as the shell.

_Dimensions._--Shell 0.07 long, 0.09 broad; horn and odd caudal foot 0.04 long; pectoral feet 0.16, tergal 0.08 long.

_Habitat._--South Pacific, Station 297, depth 1775 fathoms.

2. _Clathrospyris pyramidalis_, n. sp. (Pl. 95, fig. 9).

Shell four-sided pyramidal, truncate, thorny, with a slight sagittal stricture. Pores very large, polygonal roundish. Two pairs of large pores on each side of the ring (at the frontal and the occipital plate). Lateral pores more numerous. Basal plate with four large pores. The four edges of the pyramid are prolonged into four short pyramidal divergent lateral feet (one-third as {1053}long as the shell). Caudal foot short. Horn at the apex of the truncate pyramid with two lateral teeth.

_Dimensions._--Shell 0.06 long, 0.08 broad; horn and feet 0.02 long.

_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.

3. _Clathrospyris fusiformis_, n. sp.

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.

_Dimensions._--Shell 0.07 long, 0.09 broad; pectoral feet 0.1 long.

_Habitat._--North Pacific, Station 244, depth 2900 fathoms.

5. _Aegospyris caprina_, n. sp. (Pl. 86, fig. 8).

Shell nut-shaped, papillate, with sharp sagittal stricture. Pores irregular roundish, two pairs of larger pores on each side of the ring. Basal plate with six large pores. Eight spines all straight, subvertical and nearly parallel, cylindro-conical. Two frontal horns and two tergal feet about as long as the shell; odd horn shorter; odd foot longer. Two pectoral feet twice as long as the shell, club-shaped, with a spinulate knob at the distal end.

_Dimensions._--Shell 0.06 long, 0.09 broad; pectoral feet 0.11 long.

_Habitat._--Central Pacific, Station 271, surface.

Genus 458. _Pentaspyris_,[76] Haeckel, 1881, Prodromus, p. 442.

_Definition._--#Zygospyrida# with five basal feet, without apical horn.

The genus _Pentaspyris_ differs from the two preceding genera in the absence of any coryphal horn, and represents therefore the pentapodal form among the hornless Zygospyrida.

1. _Pentaspyris pentacantha_, n. sp. (Pl. 95, fig. 11).

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores irregular roundish, two pairs of larger pores on each side of the ring. Basal plate with four larger pores. All five feet {1055}cylindrical, S-shaped curved, strongly divergent, with few short branches, the two pectoral feet twice as long as the shell and the two tergal feet; odd caudal foot shorter.

_Dimensions._--Shell 0.08 long, 0.13 broad; pectoral feet 0.2 long, tergal feet 0.1, caudal foot 0.06.

_Habitat._--Central Pacific, Station 266, depth 2750 fathoms.

2. _Pentaspyris isacantha_, n. sp.

Shell subspherical, smooth, with slight sagittal stricture. Pores small, regular circular. Basal plate with six large pores (?). All five feet equal, cylindrical, C-shaped curved, slightly divergent, about as long as the shell.

_Dimensions._--Shell 0.08 long, 0.09 broad; feet 0.07 long.

_Habitat._--Central Pacific, Station 268, depth 2900 fathoms.

Subfamily 6. THEROSPYRIDA, Haeckel, 1881, Prodromus, p. 442.

_Definition._--#Zygospyrida# tetrapoda with two pairs of descending basal feet, one pair corresponding to the anterior or pectoral, the other pair to the posterior or tergal feet of the Hexaspyrida.

Genus 459. _Zygospyris_,[77] Haeckel, 1881, Prodromus, p. 442.

_Definition._--#Zygospyrida# with two pairs of lateral feet and an apical horn.

The genus _Zygospyris_ and the following three genera represent together the peculiar subfamily of Therospyrida. These always possess four basal feet, like the Tetraspyrida; but whilst in the latter group two feet are sagittal, and two lateral, in the Therospyrida there are no sagittal feet at all, but the four feet are opposed in two lateral pairs; the anterior pair corresponds to the pectoral, the posterior to the tergal feet of the Hexaspyrida and Pentaspyrida; from these latter the Therospyrida have been derived by loss of the sagittal feet.

1. _Zygospyris quadrupes_, n. sp.

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores irregular roundish, on each side of the ring two pairs of larger pores. Apical horn conical, straight. Four feet equal, straight, divergent, conical, about as long as the shell and the horn.

_Dimensions._--Shell 0.08 long, 0.11 broad; horn and feet 0.1 long.

_Habitat._--South Atlantic, Station 335, depth 1425 fathoms.

{1056}2. _Zygospyris equus_, n. sp. (Pl. 83, fig. 16).

Shell subspherical, rough, with slight sagittal stricture. Pores small and numerous, subregular circular; no larger annular pores. Apical horn cylindrical, half as long as the shell. Two pectoral feet somewhat smaller than the two tergal feet, about as long as the shell, slightly divergent, cylindrical. The distal ends of the feet and of the horn form an ovate, dimpled and spinulate cone.

_Dimensions._--Shell 0.06 long, 0.09 broad; horn 0.04 long, feet 0.06 long.

_Habitat._--Tropical Atlantic, Station 347, depth 2250 fathoms.

Genus 460. _Elaphospyris_,[78] Haeckel, 1881, Prodromus, p. 442.

_Definition._--#Zygospyrida# with two pairs of lateral feet and three coryphal horns.

The genus _Elaphospyris_ differs from the preceding _Zygospyris_, its ancestral form, in the possession of three coryphal horns (one odd apical and two paired frontal horns), and therefore bears to it the same relation that _Triceraspyris_ does to _Tripospyris_ among the Tripospyrida.

Subgenus 1. _Giraffospyris_, Haeckel, 1881, Prodromus, p. 442.

_Definition._--Feet simple, not branched nor forked.

1. _Elaphospyris heptaceros_, Haeckel.

_Ceratospyris heptaceros_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 66, Taf. xx. fig. 2.

_Giraffospyris heptaceros_, Haeckel, 1881, Prodromus, p. 442.

Shell nut-shaped, tuberculate, with slight sagittal stricture and subregular circular pores. Basal plate with four large pores. Apical horn small, conical, shorter than the two curved lateral horns, which are as long as the shell. Caudal and sternal feet small, conical, straight. Two pectoral feet slender, divergent, S-shaped, about as long as the shell.

_Dimensions._--Shell 0.05 long, 0.07 broad; horns and feet 0.02 to 0.08 long.

_Habitat._--Fossil in Barbados.

2. _Elaphospyris capricornis_, n. sp.

Shell nut-shaped, spiny, with slight sagittal stricture and numerous small circular pores. Basal plate with four large pores. Three horns slender, simple, about as long as the shell, the middle one straight, the two lateral curved. Four feet of nearly equal size, slender, curved, divergent, simple, twice as long as the shell and the horns.

_Dimensions._--Shell 0.07 long, 0.09 broad; horns 0.08 long, feet 0.15 long.

_Habitat._--Central Pacific, Station 274, depth 2750 fathoms.

{1057}Subgenus 2. _Corythospyris_, Haeckel, 1881, Prodromus, p. 443.

_Definition._--Feet branched or forked.

3. _Elaphospyris damaecornis_, n. sp. (Pl. 84, fig. 10).

Shell flat and broad, nearly triangular, with slight sagittal stricture and irregular roundish pores; two very large pores on the frontal and on the occipital face, opposite on both edges of the broad sagittal ring. Basal plate with four large central and several smaller lateral pores. Three horns about half as long as the shell, with two to six irregular branches. Four feet of equal size, about as long as the shell, divergent, forked, with four to six irregular terminal branches. (The shell in fig. 10 is seen from the apical side.)

_Dimensions._--Shell 0.09 long, 0.13 broad; horns 0.05 long, feet 0.1 long.

_Habitat._--Indian Ocean, Cocos Islands, Rabbe, surface.

4. _Elaphospyris cervicornis_, n. sp. (Pl. 86, fig. 13).

Shell polyhedral, spiny, with deep sagittal stricture and a small number of large roundish pores; two pairs of large pores on each side of the ring. Basal plate with four pores. Three large horns as long as the shell arise from the apex between smaller conical spines; the middle odd horn simple, the two lateral each with a pair of branches. Two pectoral feet very large, divergent, with broad and irregular distal ramification, twice as long as the shell and as the two tergal feet, which are less branched. (Fig. 13 exhibits the shell from the dorsal side.)

_Dimensions._--Shell 0.09 long, 0.11 broad; horns and smaller feet 0.07 to 0.09 long; pectoral feet 0.16 long.

_Habitat._--Central Pacific, Station 271, depth 2425 fathoms.

5. _Elaphospyris alcicornis_, n. sp. (Pl. 86, fig. 12).

Shell nut-shaped, spiny, with sharp sagittal stricture and large roundish pentagonally framed pores; three pairs of larger pores on each side of the ring. Basal plate with four larger and four alternate smaller pores. There arise from the apex, between smaller spines, three large, divergent, pyramidal horns, which are nearly as long as the shell, and connected by an arched frontal bridge. Two pectoral feet very large, divergent, prismatic, longer than the shell, and at the distal end with a bunch of thick spines. Two tergal feet half as long and thick, simple (in the figure hidden behind the large pectoral feet).

_Dimensions._--Shell 0.09 long, 0.11 broad; horns and smaller feet 0.06 long, pectoral feet 0.12 long.

_Habitat._--Central Pacific, Station 266, depth 2750 fathoms.

{1058}Genus 461. _Taurospyris_,[79] Haeckel, 1881, Prodromus, p. 442.

_Definition._--#Zygospyrida# with two pairs of lateral feet and one pair of lateral horns.

The genus _Taurospyris_ bears only two frontal horns in the coryphal face of the shell, and may therefore be derived from the preceding closely allied _Elaphospyris_ by reduction and loss of the middle or apical horn.

1. _Taurospyris cervina_, n. sp. (Pl. 95, fig. 12).

Shell nut-shaped, thorny, with deep sagittal stricture and irregular roundish pores; three pairs of larger pores on each side of the ring. Basal plate with four large pores. Two horns cylindrical, curved, widely divergent, about as long as the shell, branched. Four feet of nearly equal length, also cylindrical and curved, divergent, somewhat longer than the shell, in the distal half branched like a deer's antler.

_Dimensions._--Shell 0.07 long, 0.11 broad; horns 0.03 long, feet 0.06 long.

_Habitat._--South Atlantic, Station 332, depth 2200 fathoms; also fossil in Barbados.

2. _Taurospyris bovina_, n. sp.

Shell subspherical, smooth, with slight sagittal stricture and small circular pores. Basal plate with six larger pores. Two horns conical, curved, divergent, about as long as the shell. Two pectoral feet very large, twice as long as the shell and as the two thinner tergal feet; all four feet curved, cylindrical, divergent, pointed at the distal end.

_Dimensions._--Shell 0.08 long, 0.09 broad; horns and posterior feet 0.1, anterior feet 0.2 long.

_Habitat._--Tropical Atlantic, Station 347, depth 2250 fathoms.

Genus 462. _Therospyris_,[80] Haeckel, 1881, Prodromus, p. 442.

_Definition._--#Zygospyrida# with two pairs of lateral feet, without apical horn.

The genus _Therospyris_ has two pairs of lateral feet corresponding to those of the preceding three genera, but differs from them in the complete absence of horns on the coryphal face of the shell.

1. _Therospyris canis_, n. sp.

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores irregular, roundish. Basal plate with four longer pores. Surface covered with roundish tubercles. Four feet equal, divergent, about as long as the shell, thickened at the distal end, club-shaped, not forked.

_Dimensions._--Shell 0.07 long, 0.11 broad; feet 0.09 long.

_Habitat._--Fossil in Barbados.

{1059}2. _Therospyris felis_, n. sp. (Pl. 89, fig. 6).

Shell nut-shaped, mammillate, with sharp sagittal stricture. Pores large, irregularly roundish or polygonal, of somewhat different size. Basal plate with four large pores. Surface covered with hemispherical pointed mammillæ. Four feet equal, divergent, half as long as the shell, at the distal end forked, with few small branches.

_Dimensions._--Shell 0.1 long, 0.15 broad; feet 0.05 long.

_Habitat._--Central Pacific, Station 268, depth 2900 fathoms.

3. _Therospyris leo_, n. sp. (Pl. 89, fig. 5).

Shell nearly cubical, papillate, with slight sagittal stricture. Pores irregular, roundish; on each side of the ring three pairs of larger pores (the undermost the largest). Basal plate with two large pores. Surface covered with conical papillæ. Four feet equal, divergent, about as long as the shell, with an external spur in the middle, and irregularly branched spines at the distal end.

_Dimensions._--Shell 0.08 long, 0.12 broad; feet 0.09 long.

_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.

Subfamily 7. POLYSPYRIDA, Haeckel, 1881, Prodromus, p. 442.

_Definition._--#Zygospyrida# polypoda, with numerous descending basal feet (at least seven to nine, usually twelve to sixteen or more).

Genus 463. _Petalospyris_,[81] Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 54.

_Definition._--#Zygospyrida# with numerous (seven to twelve or more) basal feet and one apical horn.

The genus _Petalospyris_ and the following three genera form together the peculiar subfamily of Polyspyrida, differing from the other Zygospyrida in the multiplication of the radial feet, which descend from the basal face of the shell; they may therefore be also called "Zygospyrida multiradiata," and bear the closest relationship to the Archiphænida (or the "Monocyrtida multiradiata"). They differ, however, from the latter in the presence of the distinct sagittal stricture, characteristic of all #Spyroidea#. The number of the basal feet, which form a coronet around the margin of the basal plate, is commonly between twelve and sixteen, but often more. Their form is usually flat, lamellar, but often also more or less cylindrical or conical.

{1060}Subgenus 1. _Petalospyrantha_, Haeckel.

_Definition._--Basal plate with two large collar pores only, separated by the base of the primary ring.

1. _Petalospyris foveolata_, Ehrenberg.

_Petalospyris foveolata_, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig.
14; Abhandl. d. k. Akad. d. Wiss. Berlin, 1875, p. 80, Taf. xxii. fig.
10.

Shell campanulate, smooth, with distinct sagittal stricture and subregular circular pores. Basal plate with two large collar pores only. Apical horn and the eight feet slender, conical, slightly curved, about as long as the shell; feet somewhat divergent (often seven or nine instead of eight).

_Dimensions._--Shell diameter 0.04 to 0.05; length of the horn and the feet 0.04 to 0.05.

_Habitat._--Fossil in Barbados.

2. _Petalospyris floscula_, n. sp.

Shell nut-shaped, tuberculate, with deep sagittal stricture and subregular circular pores. Basal plate with two large triangular pores only. Apical horn slender, conical, twice as long as the shell. Twelve to sixteen feet flattened, leaf-shaped, broad, slightly divergent, as long as the shell, with truncate distal end.

_Dimensions._--Shell 0.06 long, 0.09 broad; horn 0.12 long, feet 0.05 to 0.07 long.

_Habitat._--Central Pacific, Station 266, depth 2750 fathoms.

Subgenus 2. _Petalospyrella_, Haeckel.

_Definition._--Basal plate with three large collar pores (two paired posterior cardinal, and an odd anterior sternal pore).

3. _Petalospyris triomma_, n. sp. (Pl. 87, fig. 14).

Shell nut-shaped, tuberculate, with sharp sagittal stricture and irregular roundish pores. Basal plate with three large pores and three alternate smaller. Apical horn stout, conical, half as long as the shell. Twelve to fifteen feet, divergent, curved, pointed, as long as the horn.

_Dimensions._--Shell 0.06 long, 0.08 broad; horn and feet 0.03 long.

_Habitat._--North Pacific, Station 244, depth 2900 fathoms.

4. _Petalospyris platyacantha_, Ehrenberg.

_Petalospyris platyacantha_, Ehrenberg, Abhandl. d. k. Akad. d. Wiss.
Berlin, 1875, p. 80, Taf. xxii. fig. 8.

Shell campanulate, smooth, with slight sagittal stricture and small irregular roundish pores. Basal plate with three large pores (?). Apical horn very strong, three-sided pyramidal, twice as {1061}long as the shell (its edge is described by Ehrenberg as a "canaliculus.") Feet ten to twelve, flat, triangular, vertical, about as long as the shell.

_Dimensions._--Shell 0.04 long, 0.05 broad; 0.07 long, feet 0.03 long.

_Habitat._--Fossil in Barbados.

5. _Petalospyris corona_, Stöhr.

_Petalospyris corona_, Stöhr, 1880, Palæontogr., vol. xxvi. p. 98, Taf.
iii. fig. 13.

Shell nut-shaped, smooth, with slight sagittal stricture and very numerous small circular pores; on each side of the stricture three larger annular pores (the undermost the largest). Basal plate with three large pores only. Apical horn very small, conical. Feet twelve to eighteen, short conical, nearly vertical, shorter than the half shell (in my specimen from Caltanisetta much stouter than in that of Stöhr).

_Dimensions._--Shell 0.07 long, 0.09 broad; horn and feet 0.01 to 0.03 long.

_Habitat._--Fossil in Tertiary rocks of Sicily (Grotte, Caltanisetta).

Subgenus 3. _Petalospyrissa_, Haeckel.

_Definition._--Basal plate with four collar pores (two larger posterior cardinal and two smaller anterior jugular pores).

6. _Petalospyris octopus_, n. sp. (Pl. 87, fig. 11).

Shell nut-shaped, tuberculate, with sharp sagittal stricture and irregular, roundish pores. Basal plate with four larger pores. Horn slender, conical, half as long as the shell. Feet eight, very slender, about three times as long as the shell, subvertical, with outer convex edge and convergent ends.

_Dimensions._--Shell 0.06 long, 0.09 broad; horn 0.03 long, feet 0.2 long.

_Habitat._--Tropical Atlantic, Station 342, depth 1445 fathoms.

7. _Petalospyris eupetala_, Ehrenberg.

_Petalospyris eupetala_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 80, Taf. xxii. fig. 4.

Shell nut-shaped, tuberculate, with slight sagittal stricture and scattered small circular pores. Basal plate with four large collar pores (sometimes surrounded by several small peripheral pores). Apical horn slender, conical, as long as the shell. Feet sixteen to twenty, laminated and truncate, of the same length, nearly vertical and parallel.

_Dimensions._--Shell 0.06 long, 0.08 broad; horn and feet 0.05 to 0.07 long.

_Habitat._--Fossil in Barbados.

{1062}8. _Petalospyris anthemis_, n. sp.

Shell nut-shaped, spinulate, with deep sagittal stricture and irregular, roundish pores. Basal plate with four large pores of equal size. Apical horn conical, twice as long as the shell. Feet twenty to thirty, laminated and truncate, as long as the shell, divergent.

_Dimensions._--Shell 0.05 long, 0.08 broad; horn 0.1 long, feet 0.6 long.

_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.

9. _Petalospyris tessaromma_, n. sp.

Shell subspherical, with slight sagittal stricture and few small pores; on each side of the stricture four larger, square, annular pores. Basal plate with four large collar pores (two larger cardinal and two smaller jugular pores). Horn and feet conical, about half as long as the shell. Feet twenty to twenty-five, slightly curved, convergent.

_Dimensions._--Shell diameter 0.08; horn and feet 0.04.

_Habitat._--Central Pacific, Station 268, depth 2900 fathoms; also fossil in Barbados.

Subgenus 4. _Petalospyromma_, Haeckel.

_Definition._--Basal plate with numerous (six or more) collar pores, commonly three or four larger central, and six to twelve smaller peripheral pores.

10. _Petalospyris novena_, n. sp. (Pl. 83, fig. 12).

Shell nut-shaped, tuberculate, with slight sagittal stricture and irregular, roundish pores. Basal plate with nine pores (three large primary and three alternate pairs of small secondary pores). Nine long corresponding feet, twice to four times as long as the shell (three very thick primary, and three alternate pairs of thin secondary feet). All feet cylindrical, curved, widely divergent. Horn conical.

_Dimensions._--Shell 0.06 long, 0.08 broad; horn and feet 0.15 to 0.25.

_Habitat._--Indian Ocean (Cocos Islands), Rabbe, surface.

11. _Petalospyris argiscus_, Ehrenberg.

_Petalospyris argiscus_, Ehrenberg, 1875, Abhandl. d. k. Akad. Wiss.
Berlin, p. 80, Taf. xxii. figs. 1, 2.

_Petalospyris argiscus_, Bütschli, 1882, Zeitschr. f. wiss. Zool., vol.
xxxvi. p. 539, Taf. xxxii. fig. 17, _a_, _b_.

Shell nut-shaped, tuberculate, with slight sagittal stricture and irregular, roundish pores. Basal plate with nine pores (three larger central and three alternate pairs of smaller peripheral pores). {1063}Apical horn slender, spindle-shaped, about as long as the shell. Twenty to twenty-five feet, of the same length, broad, lamellar and truncate, nearly vertical, slightly divergent.

_Dimensions._--Shell 0.06 long, 0.1 broad; horn and feet 0.05 to 0.07 long.

_Habitat._--Fossil in Barbados.

12. _Petalospyris papillata_, n. sp.

Shell nearly cubical, papillate, without external sagittal stricture, with small, irregular, roundish pores. Basal plate with six pores (three larger and three alternate smaller). Apical horn conical, half as long as the shell. Feet twenty to thirty, one-half to one-third as long, conical, divergent.

_Dimensions._--Shell diameter 0.09; horn 0.04 long, feet 0.03 to 0.05 long.

_Habitat._--North Atlantic, Station 353, depth 2965 fathoms.

13. _Petalospyris dictyocubus_, n. sp. (Pl. 86, fig. 6).

Shell nearly cubical, smooth, without external stricture, but with a complete, parietal, square, sagittal ring. On each side of the ring four pairs of larger pores, whilst the lateral pores are smaller and more numerous. Basal plate also with four pairs of larger pores and smaller lateral pores. Apical horn and basal feet short, pyramidal, scarcely one-fourth as long as the shell. The three primary feet are larger than the six to nine secondary feet.

_Dimensions._--Shell diameter 0.08; horn and feet 0.02 long.

_Habitat._--Central Pacific, Station 274, surface.

14. _Petalospyris bellidiastrum_, n. sp.

Shell nut-shaped, tuberculate, with slight sagittal stricture and irregular, roundish pores. Basal plate with twelve pores (four central larger and eight peripheral smaller pores). Apical horn slender, conical, about as long as the shell (sometimes ramified at the distal end). Feet sixteen to twenty, broadly lamellar, truncate, divergent, about as long as the shell.

_Dimensions._--Shell 0.08 long, 0.1 broad; horn and feet 0.07 to 0.09 long.

_Habitat._--Central Pacific, Station 265, depth 2900 fathoms; also fossil in Barbados.

15. _Petalospyris dinoceras_, n. sp. (Pl. 87, fig. 12).

Shell nut-shaped, mammillate, without external stricture, but with complete external sagittal ring. Pores subregular, circular. Basal plate with four large central pores, surrounded by a circle of twelve to twenty small peripheral pores. Apical horn very large, spindle-shaped, one and a half times as long as the shell. Feet twenty-five to thirty, broadly lamellar, truncate, divergent, about as long as the shell.

_Dimensions._--Shell 0.11 long, 0.13 broad; horn 0.15 long, feet 0.09 long.

_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.

{1064}16. _Petalospyris furcata_, n. sp.

Shell nut-shaped, smooth, with sharp sagittal stricture. Pores numerous, small, and circular; no larger annular pores. Basal plate with four larger and four alternate pairs of smaller pores. Horn conical, about as long as the shell. Feet fifteen to twenty, broadly lamellar, about twice as long as the shell, in the distal half forked.

_Dimensions._--Shell 0.04 long, 0.06 broad; horn 0.05 long, feet 0.1 long.

_Habitat._--South Pacific, Station 300, depth 1375 fathoms.

17. _Petalospyris lobata_, n. sp. (Pl. 87, fig. 13).

Shell subspherical, smooth, with slight sagittal stricture. Pores small, roundish; on each side of the ring two pairs of larger annular pores. Basal plate with four pores. Horn stout, three-sided prismatic, half as long as the shell. Feet twelve to sixteen, lamellar, lobate (the most part with three lobes), nearly vertical, about as long as the shell.

_Dimensions._--Shell diameter 0.05; horn 0.03, feet 0.05 long.

_Habitat._--South Atlantic, Station 335, depth 1425 fathoms.

Genus 464. _Anthospyris_,[82] Haeckel, 1881, Prodromus, p. 443.

_Definition._--#Zygospyrida# with numerous (seven to nine or more) basal feet and three coryphal horns.

The genus _Anthospyris_ differs from the preceding _Petalospyris_, its ancestral form, in the possession of three horns on the coryphal face (one odd middle apical horn and two paired frontal horns, one on each side). The former therefore bears to the latter the same relation that _Triceraspyris_ does to _Tripospyris_ and _Liriospyris_ to _Hexaspyris._

1. _Anthospyris mammillata_, n. sp. (Pl. 87, fig. 16).

Shell nut-shaped, mammillate, with deep sagittal stricture and irregular, polygonal pores. Basal plate with two large ovate pores (?). The pediculate apical horn and the two frontal horns stout and short, conical, twice to three times as large as the conical papillæ of the surface. Feet twelve to fifteen, lanceolate lamellar, pointed, divergent, about as long as the shell.

_Dimensions._--Shell 0.05 long, 0.08 broad; horns 0.03, feet 0.04 long.

_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.

{1065}2. _Anthospyris spathulata_, n. sp. (Pl. 87, fig. 15).

Shell subspherical, thorny, with slight sagittal stricture and irregular, roundish pores. Basal plate with three large pores. The three horns spindle-shaped, half as long as the ten to twelve thin feet, which are pediculate, shovel-shaped, a little divergent, and shorter than the shell.

_Dimensions._--Shell 0.05 diameter; horn 0.02 long, feet 0.04 long.

_Habitat._--North Pacific, Station 250, depth 3050 fathoms.

3. _Anthospyris diaboliscus_, Haeckel.

_Petalospyris diaboliscus_, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig.
12; Abhandl. d. k. Akad. d. Wiss. Berlin, 1875, p. 80, Taf. xxii. fig. 3.

Shell nut-shaped, smooth, with slight sagittal stricture and small circular pores. Basal plate with four large pores. Apical horn straight conical, frontal horns curved laterally. Feet nine to twelve, of about the same length as the horns and the shell, broad lamelliform, truncate, nearly vertical, slightly curved.

_Dimensions._--Shell 0.04 long, 0.07 broad; horns and feet 0.05 to 0.07 long.

_Habitat._--Fossil in Barbados.

4. _Anthospyris arachnoides_, Haeckel.

_Petalospyris arachnoides_, Haeckel, 1862, Monogr. d. Radiol., p. 294,
Taf. xii. fig. 7.

Shell nut-shaped, tuberculate, with slight sagittal stricture and irregular, polygonal pores. Basal plate with four large pores (?). Apical horn straight, conical, longer than the two curved lateral horns. Feet ten, slender, S-shaped, widely divergent, about as long as the shell is broad.

_Dimensions._--Shell 0.05 long, 0.08 broad; horns 0.03 to 0.05 long, feet 0.08 long.

_Habitat._--Mediterranean (Messina), Atlantic, Station 354, surface.

5. _Anthospyris aculeata_, n. sp. (Pl. 86, fig. 5).

Shell campanulate, spiny, with deep sagittal stricture and irregular, roundish pores. On each side of the stricture three pairs of larger annular pores. Basal plate with two large square pores. The three horns of the same size as, and similar form to, the ten to fifteen feet, slender pyramidal, straight, divergent, about half as long as the shell. (This species is very variable and closely allied to _Ceratospyris_.)

_Dimensions._--Shell diameter 0.08 to 0.12; horns and feet 0.04 to 0.06 long.

_Habitat._--Central Pacific, Stations 266 to 274, surface.

6. _Anthospyris doronicum_, n. sp. (Pl. 87, fig. 18).

Shell nut-shaped, spiny, with a deep sagittal stricture and small circular pores. On each side of the stricture two pairs of very large square annular pores. Basal plate with four larger collar {1066}pores and a corona of numerous small peripheral pores. Three horns spindle-shaped, divergent, about half as long as the shell. Feet twenty-five to thirty, broad, lamellar, lanceolate, pointed, divergent, nearly as long as the shell.

_Dimensions._--Shell 0.1 long, 0.13 broad; horns 0.06, feet 0.09 long.

_Habitat._--South Pacific, Station 296, depth 1825 fathoms.

7. _Anthospyris tragopogon_, n. sp. (Pl. 87, fig. 17).

Shell nut-shaped, tuberculate, with distinct sagittal stricture and small regular circular pores. Basal plate with numerous small pores. Apical horn very large, spindle-shaped, twice as long as the shell; frontal horns small, scarcely one-fourth as long, curved laterally. Feet twenty-five to thirty, three to four times as long as the shell, lamellar, lanceolate, pointed, parallel, vertical.

_Dimensions._--Shell 0.08 long, 0.11 broad; apical horn 0.16, feet 0.2 long.

_Habitat._--Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

Genus 465. _Ceratospyris_,[83] Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 54.

_Definition._--#Zygospyrida# with numerous (seven to twelve or more) basal feet and numerous coryphal horns.

The genus _Ceratospyris_ differs from all the other Zygospyrida in the possession of numerous large spines on the surface of the shell, which usually exhibits only a small number of large pores or meshes. The lower spines which cover the inferior or basal face of the shell (usually nine to twelve or more) may be compared to the descending "basal feet" of the other Zygospyrida; the upper spines, however, which cover the superior or coryphal face (usually six to nine, rarely more), may be regarded as "coryphal horns." In many species of this genus the lattice-work of the shell is of a peculiar loose kind, with few large meshes, resembling the wicker-work of the Plectanida.

Subgenus 1. _Lophospyris_, Haeckel, 1881, Prodromus, p. 443.

_Definition._--Spines simple, not branched. Meshes of the shell usually polygonal, or roundish with polygonal frames. Bars of the network prismatic.

1. _Ceratospyris polygona_, n. sp. (Pl. 86, fig. 1).

Shell polyhedral, with deep sagittal stricture, studded with twenty-four to thirty long simple straight slender pyramidal spines, which are as long as the shell or longer. All pores large, polygonal. On the frontal and the occipital face two pairs of very large pores only, the superior {1067}pentagonal, larger than the inferior tetragonal. Basal plate with two triangular pores. Bars of the loose framework three-sided prismatic, thin.

_Dimensions._--Shell 0.08 long, 0.12 broad; spines 0.06 to 0.12 long.

_Habitat._--Cosmopolitan; Atlantic, Indian, Pacific, surface.

2. _Ceratospyris pentagona_, Ehrenberg.

_Ceratospyris pentagona_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 287, Taf. x. fig. 15.

Shell polyhedral, with slight sagittal stricture, studded with twenty-four to thirty small simple conical spines, which are shorter than one-fourth of the shell. Most pores pentagonal. On the frontal and the occipital face two pairs of large pores only, the superior smaller than the inferior. Basal plate with four quadrangular pores. Bars of the network prismatic, thin.

_Dimensions._--Shell 0.07 long, 0.11 broad; spines 0.01 to 0.02 long.

_Habitat._--Cosmopolitan; Atlantic, Indian, Pacific, surface.

3. _Ceratospyris allmersii_, n. sp. (Pl. 86, fig. 3).

Shell polyhedral, with slight sagittal stricture, studded with thirty to forty prismatic spines which are not longer than half the shell. Most pores pentagonal. On the frontal face two, on the occipital three pairs of larger pores; the inferior the largest. Basal plate with two rhomboidal pores (?). Bars of the network three-sided prismatic, thin. Dedicated to my dear friend, the excellent poet and naturalist, Hermann Allmers, of Rechtenfleth.

_Dimensions._--Shell 0.08 long, 0.12 broad; spines 0.01 to 0.03.

_Habitat._--Tropical Atlantic, Station 347, depth 2250 fathoms.

4. _Ceratospyris mulderi_, n. sp. (Pl. 86, fig. 4).

Shell polyhedral, with deep sagittal stricture, studded with fifty to seventy prismatic spines; two inferior (pectoral) spines about as long as the shell, the others much shorter. Pores polygonal. On the frontal and the occipital face one pair of very large pores. Basal plate with two distinctly hexagonal pores. Bars of the loose network prismatic. Dedicated to my dear friend, the excellent author and painter, Ludwig Mulder, of the Hague.

_Dimensions._--Shell 0.07 long, 0.12 broad; spines 0.01 to 0.08.

_Habitat._--Indian Ocean, Sunda Straits (Rabbe), surface.

5. _Ceratospyris strasburgeri_, n. sp. (Pl. 86, fig. 2).

Shell polyhedral, with slight sagittal stricture, studded with thirty to forty prismatic spines, which are about half as long as the shell (two or four inferior are longer). Pores roundish, with polygonal frames. On the frontal and occipital face two pairs of larger pores (the superior {1068}smaller). Basal plate with two large pentagonal pores. Bars of the network prismatic. Dedicated to my dear friend, the celebrated botanist, Professor Eduard Strasburger, of Bonn.

_Dimensions._--Shell 0.07 long, 0.1 broad; spines 0.02 to 0.04.

_Habitat._--Western Tropical Pacific, Station 225, depth 4475.

6. _Ceratospyris mülleri_, Stöhr.

_Ceratospyris mülleri_, Stöhr, 1880, Palæontogr., vol. xxvi. Taf. iii.
fig. 15.

Shell polyhedral, with slight collar stricture, studded with forty to fifty pyramidal spines, shorter than half the shell. Pores circular, with pentagonal frames of the same breadth, all nearly of equal size. (Basal plate with four pores?) Bars of the network prismatic. Dedicated to Johannes Müller.

_Dimensions._--Shell 0.08 long, 0.1 broad; spines 0.01 to 0.03.

_Habitat._--Fossil in Tertiary rocks of Sicily, Grotte (Stöhr).

7. _Ceratospyris krausei_, n. sp. (Pl. 86, fig. 10).

Shell nut-shaped, with deep sagittal stricture, studded with forty to fifty strong conical spines; six basal spines as long as the shell and two to three times as long as the others. Pores roundish polygonal, twice to three times as broad as the bars; two pairs of larger pores on each side of the ring. (Basal plate with four large pores?) Bars of the network rounded, thick. Dedicated to my dear friend, the excellent author, Ernst Krause (Carus Sterne), of Berlin.

_Dimensions._--Shell 0.06 long, 0.09 broad; spines 0.03 to 0.08.

_Habitat._--Western Tropical Pacific (Philippine Sea), Station 206, depth 2100 fathoms.

8. _Ceratospyris preyeri_, n. sp. (Pl. 86, fig. 9).

Shell nut-shaped, with slight sagittal stricture, studded with ten to twelve longer club-shaped spines (about as long as the shell) and numerous smaller conical spines. Pores irregular, roundish, numerous; two pairs of larger pores on each side of the ring. Basal plate with four large pores. Bars of the network rounded. Dedicated to my honoured friend and colleague, the celebrated investigator of psychical ontogeny, Professor William Preyer, of Jena.

_Dimensions._--Shell 0.07 long, 0.09 broad; spines 0.02 to 0.08 long.

_Habitat._--South Atlantic, Station 332, depth 2200 fathoms.

9. _Ceratospyris echinus_, Ehrenberg.

_Ceratospyris echinus_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 66, Taf. xx, fig. 12.

Shell subspherical, with slight sagittal stricture, studded with numerous conical curved spines; six basal and one apical spine are larger than the others, about as long as the shell. Pores numerous, small, circular. Basal plate with numerous pores. Bars of the network roundish.

_Dimensions._--Shell 0.05 long, 0.06 broad; spines 0.02 to 0.05 long.

_Habitat._--Fossil in Barbados.

{1069}Subgenus 2. _Cladospyris_, Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 54.

_Definition._--Spines forked or branched. Meshes roundish or polygonal.

10. _Ceratospyris ramosa_, Ehrenberg.

_Ceratospyris ramosa_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 66, Taf. xx. fig. 7.

_Cladospyris ramosa_, Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d.
Wiss. Berlin, p. 54.

Shell nut-shaped, with slight sagittal stricture, studded with numerous conical, irregularly branched spines. The largest about as long as the shell. Pores irregular, roundish; on each side of the ring two pairs of larger pores. Basal plate with four pores. Bars of the network roundish.

_Dimensions._--Shell 0.06 long, 0.08 broad; spines 0.02 to 0.08 long.

_Habitat._--Fossil in Barbados.

11. _Ceratospyris carnerii_, n. sp. (Pl. 86, fig. 11).

Shell nut-shaped, with sharp sagittal stricture, studded with numerous pyramidal spines; two basal spines are larger, as long as the shell, and irregularly branched. Pores polygonal; on each side of the ring three pairs of larger pores. Basal plate with four large pores. Dedicated to my dear friend, the excellent monistic philosopher, B. von Carneri.

_Dimensions._--Shell 0.09 long, 0.12 broad; spines 0.02 to 0.08 long.

_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.

12. _Ceratospyris calorrhiza_, n. sp. (Pl. 87, fig. 19).

Shell nut-shaped, with deep sagittal stricture, studded with numerous conical strong spines, about one-fourth as long as the shell. Basal spines irregularly branched, with root-like ends. Pores irregular, roundish, some larger pores on each side of the ring. Basal plate with four larger pores. Bars of the network roundish.

_Dimensions._--Shell 0.1 long, 0.14 broad; spines 0.02 to 0.04 long.

_Habitat._--Central Pacific, Station 271, surface.

Genus 466. _Gorgospyris_,[84] Haeckel, 1881, Prodromus, p. 443.

_Definition._--#Zygospyrida# with numerous (seven to twelve or more) basal feet, without coryphal horns.

The genus _Gorgospyris_ agrees with the three preceding genera in the possession of numerous basal feet, but differs from them in the complete absence of any horns on the coryphal face. It represents therefore the "hornless polypedal Zygospyrida," and may {1070}be derived from _Petalospyris_ by loss of the original apical horn. The feet are commonly numerous, and often form a circle around the margin of the basal plate, similar to the circle of tentacles in many Medusæ (Gorgon).

Subgenus 1. _Gorgospyrium_, Haeckel.

_Definition._--Feet simple, not branched.

1. _Gorgospyris medusa_, n. sp. (Pl. 87, fig. 1).

Shell hemispherical, papillate, with slight sagittal stricture and subregular circular pores. Basal plate with three large collar pores (by mistake not correctly represented in the figure). Ten to twelve slender feet, twice as long as the shell, strongly curved and divergent, of equal length.

_Dimensions._--Shell 0.06 long, 0.08 broad; feet 0.1 long.

_Habitat._--North Pacific, Station 241, depth 2300 fathoms.

2. _Gorgospyris medusetta_, n. sp. (Pl. 87, fig. 2).

Shell misshaped, smooth, with deep sagittal stricture and irregular, roundish pores. Basal plate with three large collar pores, alternating with three pairs of smaller pores. Sixteen to twenty slender feet, about as long as the shell, slightly curved and divergent, of nearly equal length.

_Dimensions._--Shell 0.05 long, 0.08 broad; feet 0.05 long.

_Habitat._--Central Pacific, Station 274, depth 2750 fathoms.

3. _Gorgospyris ehrenbergii_, Haeckel.

_Petalospyris pentas_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 80, Taf. xxii. fig. 11.

Shell nut-shaped, smooth, with slight sagittal stricture and unequal circular pores. Basal plate with three large central pores, alternating with three pairs of smaller pores, and with a peripheral circle of smaller pores. Twenty-four to thirty short truncated feet, shorter than half the shell.

_Dimensions._--Shell 0.05 long, 0.07 broad; feet 0.02 long.

_Habitat._--Fossil in Barbados.

4. _Gorgospyris polypus_, n. sp. (Pl. 87, fig. 3).

Shell hemispherical, papillate, with slight sagittal stricture and subregular circular pores. Basal plate with four larger and four alternating smaller pores. Feet sixteen to twenty, slender, carved, divergent; four primary feet larger, twice to three times as long as the shell and the other feet.

_Dimensions._--Shell 0.08 long, 0.1 broad; feet 0.1 to 0.2 long.

_Habitat._--South Atlantic, Station 332, depth 2200 fathoms.

{1071}5. _Gorgospyris eurycolpos_, n. sp. (Pl. 87, fig. 5).

Shell nut-shaped, rough, with deep sagittal stricture and irregular, roundish pores; two to three pairs of larger annular pores on each side of the stricture. Basal plate with four large collar pores. Feet eight, short, triangular, vertical, about one-fourth as long as the shell.

_Dimensions._--Shell 0.08 long, 0.13 broad; feet 0.02 long.

_Habits._--Central Pacific, Station 270, depth 2925 fathoms.

6. _Gorgospyris liriope_, n. sp. (Pl. 87, fig. 6).

Shell nut-shaped, thorny, with sharp sagittal stricture and irregular, roundish pores. Two pairs of larger annular pores on each side of the ring. Basal plate with two very large circular pores only. Eight to ten short feet vertical, about one-fourth as long as the shell, with an elegant papillate knob at the distal end.

_Dimensions._--Shell 0.07 long, 0.1 broad; feet 0.02 long.

_Habitat._--South Atlantic, Station 323, depth 1900 fathoms.

7. _Gorgospyris lamellosa_, n. sp.

Shell nut-shaped, tuberculate, with subregular circular pores. Basal plate with four larger and four alternate pairs of smaller pores. Feet fifteen to twenty-five, broad, lamellar, vertical, truncate, about as long as the shell, of irregular size and form, very variable.

_Dimensions._--Shell 0.07 long, 0.1 broad; feet 0.05 to 0.1 long.

_Habitat._--Fossil in Barbados.

Subgenus 2. _Thamnospyris_, Haeckel, 1881, Prodromus, p. 443.

_Definition._--Feet divided or branched.

8. _Gorgospyris schizopodia_, n. sp. (Pl. 87, fig. 4).

Shell hemispherical, smooth, with slight sagittal stricture and small regular, circular pores. Basal plate with four large central and a circle of small pores. Feet fifteen to twenty, broad, lamellar, confluent at the base, about as long as the shell, irregularly divided or forked.

_Dimensions._--Shell 0.06 long, 0.08 broad; feet 0.05 to 0.08 long.

_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.

9. _Gorgospyris thamnopodia_, n. sp.

_Thamnospyris thamnopodia_, Haeckel, 1881, Prodromus, p. 143.

Shell nut-shaped, tuberculate, with deep sagittal stricture and irregular, roundish pores. Basal plate with numerous small pores. Feet twenty to thirty, slender, curved, divergent, twice to three times as long as the shell, irregularly branched.

_Dimensions._--Shell 0.08 long, 0.12 broad; feet 0.15 to 0.25 long.

_Habitat._--Indian Ocean (Madagascar), Rabbe, surface.

{1072}Subfamily 8. CIRCOSPYRIDA, Haeckel, 1881, Prodromus, p. 443.

_Definition._--#Zygospyrida# apoda, without descending basal feet.

Genus 467. _Circospyris_,[85] Haeckel, 1881, Prodromus, p. 444.

_Definition._--#Zygospyrida# without basal feet, with an apical horn.

The genus _Circospyris_ and the following closely allied genus _Dictyospyris_ represent together the small subfamily Circospyrida, differing from all other Zygospyrida in the absence of feet on the basal face. They have probably arisen from the Tripospyrida (_Tripospyris_) by reduction and loss of the feet (in the same way as the eradiate #Cyrtoidea# from the triradiate). But it is also possible that many of the Circospyrida (if not all) are derived directly from the Semantida (_Clathrocircus_) by the closing of the two lateral openings and by completing the framework.

1. _Circospyris nucula_, n. sp. (Pl. 95, fig. 13).

Shell nut-shaped, compressed, smooth, with prominent sagittal ring. On each side of the ring three to four pairs of very large annular polygonal pores. Lateral pores small and numerous, roundish. Basal plate with two large pores only. Horn slender, conical, shorter than half the shell.

_Dimensions._--Shell 0.11 long, 0.13 broad.

_Habitat._--Tropical Atlantic, Station 347, depth 2250 fathoms.

2. _Circospyris gigas_, Haeckel.

_Dictyospyris gigas_, Ehrenberg, Abhandl. d. k. Akad. d. Wiss. Berlin, p.
68, Taf. xix. fig. 6.

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.

{1073}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.

The genus _Dictyospyris_, the last and simplest of the twenty-eight genera of Zygocyrtida, may be regarded either as a primordial ancestral form of this large family, or more probably as the last and most reduced form of it. In the former case the total absence of coryphal horns and basal feet is primary, in the latter case secondary, effected by phylogenetic reduction and loss. But it is also possible that in one part of the numerous species of this genus the former case, and in another the latter takes place, and that one part of _Dictyospyris_ may be directly developed from the Semantida or Coronida (the lattice shell becoming complete), another part arising from the Tripospyrida or Dipospyrida (the horns and feet becoming lost).

Subgenus 1. _Dictyospyrantha_, Haeckel.

_Definition._--Basal plate with two large pores only (the primary jugular pores of _Semantis_).

1. _Dictyospyris distoma_, n. sp. (Pl. 89, figs. 11, 12).

Shell nut-shaped, smooth, or somewhat tuberculate, with deep sagittal stricture. Pores not numerous, large, roundish-polygonal; three pairs of large annular pores on each side of the ring. Basal plate with two very large pentagonal roundish collar pores.

_Dimensions._--Shell 0.06 long, 0.08 broad.

_Habitat._--Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

2. _Dictyospyris stalactites_, n. sp. (Pl. 89, fig. 7).

Shell nut-shaped, covered with irregular ramified tubercles (like stalactites), with deep sagittal stricture. Pores not numerous, large, irregular, roundish. Two pairs of large triangular pores on each side of the ring (the inferior larger). Basal plate with two very large semicircular collar pores.

_Dimensions._--Shell 0.07 long, 0.09 broad.

_Habitat._--Central Pacific, Station 272, depth 2600 fathoms; also fossil in Barbados.

{1074}3. _Dictyospyris biloba_, n. sp.

Shell subspherical, tuberculate, with slight sagittal stricture. Pores very numerous, small, circular. No larger pores on either side of the ring. Basal plate with two very large circular pores, surrounded by a circle of smaller pores.

_Dimensions._--Shell 0.07 long, 0.08 broad.

_Habitat._--North Pacific, Station 253, depth 3125 fathoms.

Subgenus 2. _Dictyospyrella_, Haeckel.

_Definition._--Basal plate with three large collar pores (two paired posterior cardinal pores and an odd anterior sternal pore).

4. _Dictyospyris triomma_, n. sp.

Shell nut-shaped, smooth, with deep sagittal stricture. Pores not numerous, large, polygonal roundish, two pairs of very large annular pores on each side of the ring. Basal plate with three large triangular pores. No free internal procolumella.

_Dimensions._--Shell 0.06 long, 0.09 broad.

_Habitat._--Indian Ocean, Zanzibar (Pullen), depth 2200 fathoms.

5. _Dictyospyris tristoma_, Ehrenberg.

_Dictyospyris tristoma_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, Taf. xix. fig. 9.

Shell nut-shaped, tuberculate, with slight sagittal stricture. Pores numerous, irregular, roundish. Three pairs of larger annular pores on each side of the ring. Basal plate with three large semi-circular pores (the sternal odd pore apparently halved by an internal free procolumella).

_Dimensions._--Shell 0.05 long, 0.08 broad.

_Habitat._--Fossil in Barbados and Sicily (Caltanisetta).

6. _Dictyospyris triloba_, Ehrenberg.

_Dictyospyris triloba_, Ehrenberg, 1876, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, Taf. xix. fig. 8.

Shell nut-shaped, spinulate, without external stricture, but with a complete internal sagittal ring. Pores numerous, subregular circular; no larger annular pores. Basal plate with three large, heart-shaped two-lobed collar pores.

_Dimensions._--Shell 0.05 long, 0.07 broad.

_Habitat._--Fossil in Barbados.

{1075}7. _Dictyospyris gigas_, Bütschli.

_Dictyospyris gigas_, Bütschli, 1880, Zeitschr. f. wiss. Zool., vol.
xxxvi., p. 539, Taf. xxxii. fig. 14_a_, 14_b_.

Shell subspherical, smooth, with a half (ventral) sagittal stricture, and a nearly complete internal ring. Pores very numerous and small, circular. No larger annular pores. Basal plate with three large collar pores (the sternal odd pore apparently divided into two jugular pores by the visible free procolumella.) (Compare _Circospyris gigas_, p. 1072 = _Dictyospyris gigas_, Ehrenberg).

_Dimensions._--Shell 0.1 long, 0.14 broad.

_Habitat._--Fossil in Barbados.

Subgenus 3. _Dictyospyrissa_, Haeckel.

_Definition._--Basal plate with four large collar pores (two larger posterior cardinal and two smaller anterior jugular pores).

8. _Dictyospyris fenestra_, Ehrenberg.

Dictyospyris fenestra, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 68, Taf. xix. fig. 11.

Shell nearly cubical, smooth, without external sagittal stricture. Internal sagittal ring complete. Pores small, roundish; on each side of the ring two crossed pairs of large, square, equal, annular pores. Basal plate also with four longer pores of nearly equal size.

_Dimensions._--Shell 0.05 long, 0.07 broad.

_Habitat._--Fossil in Barbados.

9. _Dictyospyris tetrastoma_, Ehrenberg.

_Dictyospyris tetrastoma_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, Taf. xix. fig. 12.

Shell nut-shaped, tuberculate, with slight sagittal stricture. Pores numerous, irregular, roundish. No larger annular pores. Basal plate with four large ovate collar pores (the two cardinal twice as large as the two jugular pores).

_Dimensions._--Shell 0.05 long, 0.07 broad.

_Habitat._--Cosmopolitan; Atlantic, Indian, Pacific; also fossil in Barbados and Sicily.

10. _Dictyospyris spinulosa_, Ehrenberg.

Dictyospyris spinulosa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, Taf. xix. fig. 13.

? _Ceratospyris borealis_, Bailey, 1856, Amer. Journ. of Science and
Arts, vol. xxii. pl. i. fig. 3.

Shell nut-shaped, spinulate, without external stricture, with an internal free sagittal ring. Pores numerous, irregular, roundish; on each side of the ring two pairs of very large square pores. Basal plate with four large collar pores.

{1076}_Dimensions._--Shell 0.07 long, 0.08 broad.

_Habitat._--Central Pacific, Stations 271 to 274, depth 2350 to 2750 fathoms; also fossil in Barbados.

11. _Dictyospyris mammillaris_, n. sp. (Pl. 89, figs. 9, 10).

Shell mammillate, nut-shaped, with deep sagittal stricture. Mammillæ of the surface hemispherical, with a conical apex. Pores not numerous, large, roundish. Two pairs of large pores on each side of the ring. Basal plate with four large pores.

_Dimensions._--Shell 0.06 long, 0.08 broad.

_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.

12. _Dictyospyris anthophora_, n. sp. (Pl. 89, fig. 8).

Shell tuberculate, nut-shaped, nearly cubical, without external sagittal strictures. Pores not numerous, large, polygonally roundish. Bars between them compressed, elevated, with large, campanulate or flower-like tubercles on the nodal points. Basal plate with four large pores.

_Dimensions._--Shell 0.07 long, 0.09 broad.

_Habitat._--North Atlantic, Station 349, depth 2450 fathoms.

13. _Dictyospyris quadriloba_, n. sp.

Shell nut-shaped, smooth, with deep sagittal stricture. Pores numerous, small, circular, on each side of the ring three to four times as large as on the lateral sides. Basal plate with four very large collar pores and a circle of twenty to twenty-five very small peripheral pores.

_Dimensions._--Shell 0.08 long, 0.11 broad.

_Habitat._--Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

14. _Dictyospyris messanensis_, J. Müller.

_Dictyospyris messanensis_, J. Müller, 1858, Abhandl. d. k. Akad. d.
Wiss. Berlin, p. 46, Taf. ii. fig. 8.

_Dictyospyris messanensis_, Haeckel, 1862, Monogr. d. Radiol., p. 291.

Shell nut-shaped, spinulate, with deep sagittal stricture. Pores numerous and small, irregular roundish. No larger annular pores on the sides of the ring. Basal plate with four large, nearly equal, pear-shaped collar pores.

_Dimensions._--Shell 0.06 long, 0.08 broad.

_Habitat._--Mediterranean; Messina, surface.

Subgenus 4. _Dictyospyromma_, Haeckel.

_Definition._--Basal plate with six or more collar pores.

{1077}15. _Dictyospyris hexastoma_, n. sp.

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores small, irregular, roundish. Three pairs of larger pores on each side of the ring. Basal plate with six large pores; the middle pair (cardinal) twice as large as the anterior (jugular) and the posterior (cervical).

_Dimensions._--Shell 0.08 long, 0.12 broad.

_Habitat._--Fossil in Barbados.

16. _Dictyospyris enneastoma_, n. sp.

Shell ellipsoidal, smooth, without external sagittal stricture, but with an internal free sagittal ring. Pores small and numerous, regular, circular. No larger annular pores. Basal plate with nine pores, three larger interradial alternating with three pairs of adradial.

_Dimensions._--Shell 0.07 long, 0.11 broad.

_Habitat._--South Pacific, Station 297, depth 1775 fathoms.

17. _Dictyospyris polystoma_, n. sp.

Shell nut-shaped, mammillate, with distinct sagittal stricture. Pores small and numerous, irregular, on each side of the ring three to five times as large as on the lateral sides. Basal plate with twelve large pores (four central and four alternate pairs of peripheral).

_Dimensions._--Shell 0.1 long, 0.14 broad.

_Habitat._--Tropical Atlantic, Station 338, depth 1990 fathoms.

Family LIII. #THOLOSPYRIDA#, n. fam.

(Pl. 87, figs. 7-10; Pl. 89, figs. 1-4; Pl. 95, figs. 14-16).

_Definition._--#Spyroidea# with a galea, but without thorax; the shell being composed of the bilocular cephalis and of an aboral cupola or galea arising from its coryphal face.

The family #Tholospyrida# differs from the preceding Zygospyrida, its ancestral group, in the development of a galea, _i.e._, a fenestrated hemispherical or dome-shaped cupola, which covers the upper face of the cephalis like a cap.

Only three species of this family have been hitherto described: _Pylospyris_ (or _Spyridobotrys_) _trinacria_, figured in my Monograph (1862), _Pylospyris_ (or _Lithopera_) _denticulata_, figured by Ehrenberg (1872), and _Lophospyris_ (or _Ceratospyris_) _acuminata_, figured by Hertwig (1879). Fourteen new species have been found in the collection of the Challenger, which we dispose here among five genera. These may be derived from corresponding genera of Zygospyrida by the development of a galea.