Definition.—Pores of the cortical shell irregular, of different size and form; spines covering the entire surface (commonly one spine at each nodal-point).
20. Haliomma capillaceum, Haeckel.
Haliomma capillaceum, Haeckel, 1862, Monogr. d. Radiol., p. 426, Taf. xxiii. fig. 2.
Cortical shell very thin walled, seven to eight times as broad as the medullary shell, both with irregular, polygonal pores, and very thin thread-like bars; outer pores twice to three times as broad as the inner. Radial spines very numerous, straight, bristle-shaped, about as long as the diameter of the medullary shell.
Dimensions.—Diameter of the outer shell 0.2, inner 0.025 to 0.03; outer pores 0.02 to 0.04, inner 0.008 to 0.016, bars 0.001; length of the spines 0.02 to 0.03.
Habitat.—Mediterranean (Messina), Atlantic (Canary Islands), surface.
21. Haliomma erinaceum, Haeckel.
Haliomma erinaceum, Haeckel, 1862, Monogr. d. Radiol., p. 427, Taf. xxiii. figs. 3, 4.
Cortical shell thin walled, seven to eight times as broad as the medullary shell, both with irregular, polygonal pores, two to ten times as broad as the bars, outer pores much larger than the inner. Radial spines very numerous, bristle-shaped, as long as the diameter of the medullary shell, the majority or all being either curved or obliquely depressed, the greater part neither straight nor radial.
Dimensions.—Diameter of the outer shell 0.2, inner 0.025 to 0.03; outer pores 0.005 to 0.03, inner 0.008 to 0.016, bars 0.002 to 0.004; length of the spines 0.03.
Habitat.—Cosmopolitan; Mediterranean, Atlantic, Pacific, surface.
22. Haliomma tenellum, Haeckel.
Haliomma tenellum, Haeckel, 1862, Monogr. d. Radiol., p. 428.
Haliomma spinuloso affine, J. Müller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 40, Taf. iv. fig. 7.
Cortical shell thin walled, three times as broad as the medullary shell, with irregular, roundish pores, and very thin bars. Pores of the inner shell regular, circular. Radial spines very numerous, bristle-shaped, straight, as long as the radius of the outer shell.
Dimensions.—Diameter of the outer shell 0.15, inner 0.05; outer pores 0.008 to 0.016, inner 0.005; length of the spines 0.07.
Habitat.—Mediterranean (Nice); Atlantic, Stations 349 to 354, surface.
23. Haliomma spinulosum, J. Müller.
Haliomma spinulosum, J. Müller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 39, Taf. iv. fig. 6.
Cortical shell thin walled, twice as broad as the medullary shell, with irregular, polygonal pores, and very thin bars. Pores of the inner shell subregular, hexagonal, ten to twelve times as broad as the bars. Radial spines very numerous, bristle-shaped, one-sixth to one-fourth as long as the radius of the outer shell.
Dimensions.—Diameter of the outer shell 0.16, inner 0.08; outer pores 0.01 to 0.03, inner 0.02; length of the spines 0.02 to 0.03.
Habitat.—Mediterranean (Nice); Central Pacific, Station 266, surface.
24. Haliomma rhodococcus, n. sp. (Pl. 19, fig. 6).
Sethosphæra rhodococcus, Haeckel, 1879, Atlas, pl. xix. fig. 6.
Cortical shell very thin walled, little larger than the thick walled medullary shell (= 10 : 9). Pores of the outer shell very irregular, roundish, twice to six times as broad as the bars, about twenty on the radius. Pores of the inner shell twice as broad as the bars, six to eight on the radius, very regular, circular on the inner, six-lobed on the outer opening, separated by prominent hexagonal crests; in the hexagon-corners arise short conical radial spines, which at equal distances from the centre are united by the outer shell, but are prominent over its surface. (A very peculiar form; the two shells may better be regarded as inner and outer cortical shell.)
Dimensions.—Diameter of the outer shell 0.2, inner 0.18; outer pores 0.04 to 0.012, inner 0.01; length of the spines 0.01.
Habitat.—Tropical Atlantic, Station 338, depth 1990 fathoms; also fossil in Barbados.
25. Haliomma boreale, n. sp.
Cortical shell thick walled, four times as broad as the medullary shell, with irregular, roundish pores, twice to four times as broad as the bars; eight to ten on the radius. Pores of the inner shell regular, circular, twice as broad as the bars, four to six on the radius. Radial spines very numerous, conical, nearly as long as the diameter of the shell.
Dimensions.—Diameter of the outer shell 0.24, inner 0.06; outer pores 0.008 to 0.02, bars 0.005, inner pores 0.006, bars 0.003; length of the spines 0.2.
Habitat.—Arctic Ocean, Greenland ("Alert" Expedition).
Definition.—Pores of the cortical shell irregular, of different size and form; spines not covering the entire surface, but scattered at intervals (their number smaller than that of the nodal-points in the network).
26. Haliomma macrodoras, n. sp. (Pl. 28, figs. 6, 6a).
Cortical shell thin walled, twice as broad as the medullary shell, with irregular, polygonal meshes, three to six times as broad as the bars. Inner shell with regular, hexagonal meshes, ten times as broad as the bars. Twenty radial spines, very long, stout, three-sided prismatic, two to four times as long as the diameter of the shell, as broad as one medullary mesh, with three wing-like, denticulated edges. At the base of each spine three supporting curved beams.
Dimensions.—Diameter of the outer shell 0.14 to 0.16, of the inner 0.07 to 0.08; outer pores 0.01 to 0.02, bars 0.003; inner pores 0.01, bars 0.001; length of the spines 0.3 to 0.6, breadth 0.01.
Habitat.—Central Pacific, Station 271, surface.
27. Haliomma antarcticum, n. sp.
Cortical shell very thin walled, three times as broad as the medullary shell, with irregular, polygonal pores, and very thin thread-like bars. Inner shell with regular, hexagonal meshes, six times as broad as the bars. About forty radial spines, angular, pyramidal, half as long as the radius of the shell, as broad at the base as the largest mesh.
Dimensions.—Diameter of the outer shell 0.2, of the inner 0.07; outer pores 0.006 to 0.015, inner 0.008; length of the spines 0.05, basal breadth 0.012.
Habitat.—Antarctic Ocean, Station 154, surface.
28. Haliomma wyvillei, Haeckel.
Haliomma wyvillei, Haeckel, 1878, Protistenreich, p. 44, fig. 31.
Haliomma species, Wyville Thomson, 1877, Atlantic, vol. i. p. 236, fig. 54.
Cortical shell thin walled, three times as broad as the medullary shell. Both shells with irregular, large, polygonal pores, and very thin bars. From the inner shell arise very numerous (eighty to one hundred and twenty or more) radial spines, which pierce the outer shell, and are outside it, as long as the radius of the inner shell, straight, bristle-shaped, and as thick as the bars.
Dimensions.—Diameter of the outer shell 0.18, of the inner 0.06; pores 0.01 to 0.02, bars 0.001 to 0.002; length of the free spines 0.06.
Habitat.—Central Pacific, Stations 266 to 274, surface.
29. Haliomma beroes, Ehrenberg.
Haliomma beroes, Ehrenberg, 1854, Mikrogeol., Taf. xxxvB. B. iv. fig. 19.
Haliomma beroes, Haeckel, 1862, Monogr. d. Radiol., p. 434.
Cortical shell thin walled, three times as broad as the medullary shell, with irregular, roundish pores, twice to four times as broad as the bars. Inner shell with regular, circular pores, twice as broad as the bars. Both shells connected by four (or six ?) radial beams, perpendicularly crossed. Thirty to forty radial spines, conical, thin, shorter than the radius.
Dimensions.—Diameter of the outer shell 0.11, inner 0.04; outer pores 0.007 to 0.012, inner 0.005; length of the spines 0.03, basal breadth 0.005.
Habitat.—Atlantic, depth 2000 fathoms.
30. Haliomma compactum, n. sp. (Pl. 28, figs. 5, 5a).
Cortical shell very thick walled, four times as broad as the thin walled medullary shell; pores of the former irregular, roundish, with high polygonal frames of very different size, twice to four times as broad as the bars. Inner shell with simple, small, polygonal pores, connected with the outer shell by eight (?) regularly disposed thin radial beams, opposite in pairs, prolonged outside into strong conical spines, longer than the radius.
Dimensions.—Diameter of the outer shell 0.08, inner 0.02; outer pores 0.005 to 0.01, inner 0.005; length of the spines 0.06, basal breadth 0.012.
Habitat.—Central Pacific, Stations 265 to 272, depth 2425 to 2925 fathoms.
31. Haliomma permagnum, n. sp.
Cortical shell thick walled, six times as broad as the medullary shell, with irregular, roundish, double-edged pores, three to six times as broad as the bars. Inner shell with regular, circular pores, twice as broad as the bars. One hundred and twenty to one hundred and fifty radial spines, conical, only one-fourth as long as the radius.
Dimensions.—Diameter of the outer shell 0.42, inner 0.07; outer pores 0.012 to 0.025, bars 0.004; inner pores 0.008, bars 0.004; length of the spines 0.05, basal breadth 0.03.
Habitat.—Central Pacific, Station 268, surface.
32. Haliomma patagonicum, n. sp.
Cortical shell thick walled, four times as broad as the medullary shell, with irregular, roundish pores, twice to three times as broad as the bars. Inner shell also with irregular, roundish pores, of half the size. Forty to fifty radial spines, cylindro-conical, about as long as the shell diameter.
Dimensions.—Diameter of the outer shell 0.24, inner 0.06; outer pores 0.012 to 0.02, bars 0.006; inner pores 0.005 to 0.01, bars 0.004; length of the spines 0.3, breadth 0.02.
Habitat.—South-east Pacific, west coast of Patagonia, Station 302, surface.
33. Haliomma clavatum, n. sp.
Cortical shell thick walled, three times as broad as the medullary shell, with irregular, roundish pores little larger than the bars; eight to twelve on the radius. Inner shell with similar but smaller pores. About twenty radial spines, club-shaped, as long as the radius, three-sided, with prominent edges, twice as broad at the distal end as at the base. (Similar to Acanthosphæra clavata, Pl. 26, fig. 8, but differs from it in the possession of a medullary shell.)
Dimensions.—Diameter of the outer shell 0.2, inner 0.06; outer pores and bars 0.008 to 0.02, inner 0.006 to 0.01; length of the spines 0.1, distal breadth 0.03.
Habitat.—Central Pacific, Station 265, depth 2900 fathoms.
Definition.—Astrosphærida with one medullary (intracapsular) and one cortical (extracapsular) shell, the two being connected by radial beams piercing the central capsule. Shell surface covered with simple radial spines of two different kinds; larger main spines and smaller by-spines.
The genus Heliosoma differs from the preceding Haliomma in the possession of two different kinds of radial spines, and exhibits therefore the same relation to it that Heliosphæra bears to Acanthosphæra among the Coscinommida. The smaller by-spines are much more numerous than the larger main spines.
Definition.—Pores of the cortical shell regular, of nearly equal size and similar form.
1. Heliosoma radians, n. sp. (Pl. 28, figs. 3, 3a).
Cortical shell very thin walled, with thread-like bars and regular, hexagonal meshes; twenty to twenty-two on the radius. Medullary shell only one-fifth as large, of the same structure. The two shells connected by twenty very thin radial beams, which are prolonged outside into twenty stout, three-sided pyramidal main spines, as long as the diameter of the inner shell. Between these, arising from the surface, numerous bristle-shaped by-spines.
Dimensions.—Diameter of the outer shell 0.25, inner 0.05, pores 0.012; length of the main spines 0.05, basal breadth 0.012.
Habitat.—Central Pacific, Stations 266 to 274, surface.
2. Heliosoma elegans, n. sp.
Cortical shell thick walled, with regular, circular, hexagonally framed pores, twice as broad as the bars; ten to twelve on the radius. Medullary shell half as large, with simple, regular, circular pores, twice as broad as the bars. The two shells connected by twenty very thin radial beams, which are prolonged outside into twenty slender, three-sided pyramidal main spines as long as the radius. In each corner of the surface hexagons a bristle-shaped by-spine one-fourth as long.
Dimensions.—Diameter of the outer shell 0.12, inner 0.06; outer pores 0.006, bars 0.003; length of the main spines 0.05, basal breadth 0.01.
Habitat.—Central Pacific, Station 271, surface.
3. Heliosoma echinaster, Haeckel.
Haliomma echinaster, Haeckel, 1862, Monogr. d. Radiol., p. 429, Taf. xxiv. figs. 1-3.
Cortical shell thin walled, with regular, circular, hexagonally framed pores, twice as broad as the bars; ten to twelve on the radius. Medullary shell one-fourth as large, with few irregular, large, polygonal pores and very thin thread-like bars, connected with the former by nine similar thin radial beams, which are prolonged outside into nine pyramidal main spines, as long as the radius. From each corner of the surface hexagon arises a bristle-shaped by-spine, half as long as the main spine.
Dimensions.—Diameter of the outer shell 0.16, inner 0.04; outer pores 0.008, bars 0.004; length of the main spines 0.08, basal breadth 0.01.
Habitat.—Mediterranean (Messina), surface.
4. Heliosoma duodecilla, n. sp.
Cortical shell thick walled, with regular, circular pores, of the same breadth as the bars; sixteen to eighteen on the radius. Medullary shell one-third as large, of the same structure. Twelve radial main spines, regularly disposed, cylindro-conical, longer than the shell diameter, as broad as two pores. Whole surface covered with short conical by-spines.
Dimensions.—Diameter of the outer shell 0.15, inner 0.05; outer pores and bars 0.007; length of the main spines 0.2, breadth 0.02.
Habitat.—South Atlantic, Station 333, surface.
Definition.—Pores of the cortical shell irregular, of different size and form.
5. Heliosoma hastatum, n. sp. (Pl. 28, fig. 4).
Cortical shell very thin walled, with large, irregular, polygonal meshes, three to six times as broad as the bars; four to six on the radius. Medullary shell one-third as large, with small, regular, circular pores. The two shells connected by twelve regularly disposed radial beams, which are prolonged outside into twelve very stout three-sided pyramidal main spines, somewhat longer than the radius, spear-shaped; each of the three wings in the middle part with one tooth. Scattered on the surface numerous by-spines of the same form, half as long and only one-fourth as broad.
Dimensions.—Diameter of the outer shell 0.1, inner 0.033; outer pores 0.006 to 0.013, inner pores 0.002, bars 0.002; length of the main spines 0.06, breadth 0.015.
Habitat.—Central Pacific, Station 271, depth 2425 fathoms.
6. Heliosoma indicum, n. sp.
Cortical shell thick walled, with irregular, roundish pores, twice to five times as broad as the bars. Medullary shell of the same structure, only one-fourth as large. Thirty to forty conical main spines, as long as the radius; between them numerous bristle-shaped by-spines, only half as long.
Dimensions.—Diameter of the outer shell 0.2, inner 0.05; outer pores 0.004 to 0.01, bars 0.002; length of the main spines 0.1, breadth 0.01.
Habitat.—Indian Ocean, between Aden and Socotora, surface, Haeckel.
Definition.—Astrosphærida with one medullary (intracapsular) and one cortical (extracapsular) shell, the two being connected by radial beams piercing the central capsule. Shell surface covered with branched radial spines.
The genus Elatomma differs from Haliomma in the ramification of the radial spines, and exhibits therefore the same relation to it that Cladococcus, among the Coscinommida, bears to Acanthosphæra.
Definition.—Pores of the cortical shell regular, of nearly equal size and similar form.
1. Elatomma pinetum, n. sp.
Cortical shell thick walled, with regular, circular, hexagonally framed pores, three times as broad as the bars. From its surface arise twenty to thirty large, three-sided prismatic, radial spines as long as the shell diameter, branched like a pine tree; on each edge of the spine five to six ramified branches, decreasing in size towards the distal end. Similar to Cladococcus pinetum (Pl. 27, figs. 1, 3), but differing in the possession of a medullary shell (one-third as large as the outer), with regular, circular pores, as broad as the bars.
Dimensions.—Diameter of the outer shell 0.2, inner 0.07; cortical pores 0.012, bars 0.004; length of the spines 0.2 to 0.24.
Habitat.—Central Pacific, Stations 266 to 272, surface.
2. Elatomma scoparium, n. sp.
Cortical shell thick walled, with regular, circular pores, twice as broad as the bars, connected with the medullary shell by twenty thin radial beams, which are prolonged outside into twenty large cylindrical radial spines somewhat longer than the radius; in the proximal half simple, in the distal half with six to nine dichotomous, irregular branches. Similar to Cladococcus scoparius (Pl. 27, fig. 2), but much larger, and with a large medullary shell (one-third as broad as the outer), and regular, circular pores.
Dimensions.—Diameter of the outer shell 0.12, inner 0.04; cortical pores 0.01, bars 0.005; length of the spines 0.08.
Habitat.—North Pacific, Station 240, surface.
Definition.—Pores of the cortical shell irregular, of different size or form.
3. Elatomma juniperinum, n. sp. (Pl. 28, fig. 8).
Cortical shell thin walled, with regular, polygonal, or roundish pores, twice to four times as broad as the bars, connected with the small medullary shell by about twenty thin radial beams. Inner shell only one-eighth as broad as the outer, with few irregular, polygonal meshes. Surface covered with very numerous (one hundred to one hundred and fifty or more) branched conical radial spines, one-third as long as the shell radius, with six to twelve short lateral branches.
Dimensions.—Diameter of the outer shell 0.2, inner 0.025; cortical pores 0.08 to 0.016, bars 0.004; length of the spines 0.04.
Habitat.—Central Pacific, Station 271, surface.
4. Elatomma penicillus, n. sp.
Cortical shell thin walled, with irregular, polygonal pores, twice to four times as broad as the bars, connected with the medullary shell by twenty (or more?) very thin beams. These are prolonged outside into twenty straight, three-sided prismatic, radial spines as long as the radius, with a brush-like bunch of six to nine short, irregularly ramified branches at the end. Medullary shell very delicate (half as broad as the outer), with regular, hexagonal meshes and thread-like bars.
Dimensions.—Diameter of the outer shell 0.15, inner 0.08; length of the spines 0.08.
Habitat.—West coast of Norway, Bergen, Haeckel.
5. Elatomma irregulare, n. sp.
Cortical shell thin walled, with irregular, polygonal, or roundish meshes, twice to six times as broad as the bars; the medullary shell of the same structure, half as broad, with smaller irregular pores. Forty to sixty curved, three-sided, radial spines, as long as the shell, with a bunch of very irregular, curved, and partly ramified branches at the distal end.
Dimensions.—Diameter of the outer shell 0.2, inner 0.1; length of the spines 0.2, breadth 0.01.
Habitat.—North Atlantic, Gulf Stream, Færöe Channel, surface, John Murray.
Definition.—Astrosphærida with two extracapsular cortical shells without by-spines, connected by long prismatic radial spines.
The genus Leptosphæra, together with the three following genera, forms the very peculiar and typical small group of Sphæroidea which we call the Diplosphærida (with four genera and twenty-four species); their shell is composed of two concentric spheres as in the three foregoing genera; but whilst in these the inner shell is an intracapsular medullary shell and the outer an extracapsular cortical shell, in the Diplosphærida both shells are extracapsular or cortical shells, therefore the inner shell of the latter corresponds to the outer of the former. The inner spherical shell of all Diplosphærida is composed of very delicate beams and large pores, which are either regular hexagonal or irregular polygonal (never roundish). From its surface arise a variable number (twenty to thirty) of stout long radial spines, which are invariably longer than the shell diameter (often two to three times as long or more), and of three-sided prismatic form, the three edges either smooth or serrate, often with three rows of lateral branches (commonly three to five branches in each row); the latter are invariably of the same form, concavely curved towards the spine, and decrease in size towards the distal end. From the three edges of each main spine in all Diplosphærida, at equal distances from the centre, arise six very thin, thread-like lateral branches (a pair from each edge) and connect the spine in a tangential direction with all neighbouring spines. In this manner the polyhedral outer shell is formed, the meshes of which therefore are always very large and triangular. Sometimes each of these primary triangular meshes becomes filled up with a secondary network, either of regular quadrangular or of irregular polygonal secondary meshes. Besides the constant twenty to thirty large main spines, in the majority of Diplosphærida bristle-shaped radial by-spines arise, either from the inner shell (Diplosphæra) or from the outer (Drymosphæra), or from both (Astrosphæra). They are absent only in Leptosphæra. Commonly the by-spines are simple, rarely forked or branched. The central capsule in the Diplosphærida is usually enclosed in the inner shell; often it completely fills up the latter, or drives out a cæcal protuberance through each mesh; but these processes rarely unite outside. The average size of the Diplosphærida, which are all pelagic organisms, is much larger than that of the other Haliommida.
Definition.—Radial spines simple, without lateral branches.
1. Leptosphæra hexagonalis, n. sp. (Pl. 19, fig. 2).
Inner shell with regular, hexagonal meshes, and very thin, thread-like bars; outer shell twice as broad, with simple triangular meshes. Radial spines with three smooth edges. (Fig. 2 represents the central capsule with numerous club-shaped saccules, prominent externally through the meshes; in the centre a large simple spherical nucleus, one-third as broad as the capsule. The skeleton of this species is identical with that of Diplosphæra hexagonalis, Pl. 19, fig. 3, but has no by-spines.)
Dimensions.—Diameter of the outer shell 0.3, of the inner 0.15.
Habitat.—Cosmopolitan; Mediterranean (Corfu), North Atlantic (Canary Islands), Tropical Pacific, surface.
2. Leptosphæra serrata, n. sp.
Inner shell with regular, hexagonal meshes, five to six times as broad as the bars; outer shell three times as broad, with simple triangular meshes. Radial spines with three serrated edges (of the same form as the main spines of Drymosphæra dendrophora, Pl. 20, fig. 1).
Dimensions.—Diameter of the outer shell 0.45, of the inner 0.15.
Habitat.—Central Pacific, Station 271, surface.
3. Leptosphæra polygonalis, n. sp.
Inner shell with irregular, polygonal meshes and very thin thread-like bars; outer shell twice as broad, with simple triangular meshes. Radial spines with three smooth edges. (Resembles Drymosphæra polygonalis, Pl. 19, fig. 1, but has no by-spines.)
Dimensions.—Diameter of the outer shell 0.35, inner 0.175.
Habitat.—North Pacific, Station 256, surface.
Definition.—Radial spines with three rows of lateral branches (one row on each edge).
4. Leptosphæra ciliata, n. sp.
Inner shell with regular, hexagonal meshes and very thin thread-like bars; outer shell three times as broad, with simple triangular meshes. Radial spines with smooth edges and three rows of simple, smooth, curved, lateral branches (six branches on each edge), similar to those of Diplosphæra gracilis.
Dimensions.—Diameter of the outer shell 0.6, inner 0.2.
Habitat.—South Atlantic, Station 325, surface.
5. Leptosphæra spinosa, Haeckel.
Diplosphæra spinosa, R. Hertwig, 1879, Organismus d. Radiol., p. 40, Taf. v. fig. 2.
Inner shell with regular, hexagonal meshes, five times as broad as the bars; outer shell three times as broad, with simple triangular meshes. Radial spines with three densely serrated edges, and with three rows of serrated, simple, curved, lateral branches (three branches on each edge). Differs from the preceding in the thicker bars and the elegantly denticulated spines and branches.
Dimensions.—Diameter of the outer shell 0.66, inner 0.22.
Habitat.—Mediterranean (Messina), R. Hertwig.
6. Leptosphæra stellata, n. sp.
Inner shell with regular, hexagonal meshes, six times as broad as the bars, each bar crossed by a transverse tangential rod, so that each mesh represents an elegant six-rayed star (as in Astrosphæra stellata, Pl. 19, fig. 5, but without radial by-spines); outer shell twice as broad, with simple triangular meshes. Radial spines with serrated edges and three rows of simple lateral branches (four branches on each edge).
Dimensions.—Diameter of the outer shell 0.44, inner 0.22.
Habitat.—Tropical Atlantic (Ascension Island), Station 343, surface.
7. Leptosphæra reticulum, n. sp.
Inner shell with irregular, polygonal meshes and very thin thread-like bars; outer shell four times as broad, also with irregular, polygonal meshes, the sides of the triangular main meshes being connected by irregular lateral ramules, forming an extremely delicate reticulum.
Dimensions.—Diameter of the outer shell 0.64, inner 0.16.
Habitat.—South Pacific, Station 291, surface.
Definition.—Astrosphærida with two extracapsular cortical shells, connected by long, prismatic, radial spines; inner shell with thin radial by-spines.
The genus Diplosphæra differs from its ancestral form Leptosphæra in the development of radial by-spines on the surface of the inner shell, the outer shell being smooth.
Definition.—Radial main spines simple, without lateral branches.
1. Diplosphæra hexagonalis, n. sp. (Pl. 19, fig. 3).
Inner shell with regular, hexagonal meshes and very thin thread-like bars; at each nodal-point one bristle-shaped by-spine; outer shell twice as broad, with simple triangular meshes. Radial spines with three smooth edges. (The radially striped central capsule, enclosed in the inner shell, envelops a large central nucleus one-third its size, fig. 3.)
Dimensions.—Diameter of the outer shell 0.36, inner 0.18.
Habitat.—Central Pacific, Stations 265 to 274, surface.
2. Diplosphæra ornata, n. sp.
Inner shell with regular, hexagonal meshes, four times as broad as the bars; outer shell three times as broad, with simple triangular meshes. Radial main spines as well as the bars of both shells very elegantly denticulated; radial by-spines (very numerous in the surface of the inner shell) smooth.
Dimensions.—Diameter of the outer shell 0.7, inner 0.24.
Habitat.—Indian Ocean, Madagascar, surface, Rabbe.
3. Diplosphæra dictyota, n. sp.
Inner shell with regular, hexagonal meshes, six times as broad as the bars; at each nodal-point one radial by-spine; outer shell two and a half times as broad, with very delicate square meshes, separated by thread-like bars which arise from the sides of the triangular main meshes. Radial main spines with three serrated edges. (Differs from the similar Diplosphæra gracilis in the simple main spines, with delicate dentition of the edges.)
Dimensions.—Diameter of the outer shell 0.5, inner 0.2.
Habitat.—North Atlantic, Canary Islands, surface.
4. Diplosphæra polygonalis, n. sp.
Inner shell with irregular, polygonal meshes and very thin thread-like bars, covered with very numerous bristle-shaped by-spines; outer shell twice as broad, with simple triangular meshes. Radial main spines with three smooth edges.
Dimensions.—Diameter of the outer shell 0.44, inner 0.22.
Habitat.—South Pacific, Station 288, surface.
Definition.—Radial main spines with three rows of lateral branches (one row on each edge).
5. Diplosphæra gracilis, Haeckel.
Diplosphæra gracilis, Haeckel, 1862, Monogr. d. Radiol., p. 354, Taf. x. fig. 1.
Inner shell with regular, hexagonal meshes and very thin bars; at each nodal-point one simple bristle-shaped radial by-spine; outer shell twice as broad, with very delicate square meshes, separated by thread-like bars which arise from the sides of the triangular main meshes. Radial spines with smooth edges and with three rows of simple curved lateral branches (four to six branches on each edge).
Dimensions.—Diameter of the outer shell 0.54, inner 0.27.
Habitat.—Mediterranean (Messina).
6. Diplosphæra denticulata, n. sp.
Inner shell with regular, hexagonal meshes, four times as broad as the bars; at each nodal-point is a simple bristle-shaped by-spine; outer shell three times as broad, with simple triangular meshes. Radial spines very strong, with dentated edges and with three rows of lateral branches (six dentated curved branches on each edge).
Dimensions.—Diameter of the outer shell 0.4, inner 0.13.
Habitat.—North Atlantic, Azores, surface.
7. Diplosphæra reticulata, n. sp.
Inner shell with regular, hexagonal meshes, five times as broad as the bars, which are densely covered with very numerous, simple bristle-shaped by-spines; outer shell four times as broad, with very numerous small irregular polygonal meshes, forming a very delicate network, and filling out the large triangular main meshes. Radial spines with three serrated edges and three rows of short curved branches (four to five branches on each edge).
Dimensions.—Diameter of the outer shell 0.6, inner 0.15.
Habitat.—North Atlantic, Gulf Stream, Færöe Channel, surface, John Murray.
8. Diplosphæra triglochin, n. sp.
Inner shell with irregular, polygonal meshes and very thin thread-like bars; outer shell three times as broad, with similar irregular polygonal meshes, filling out the large triangular main meshes. Radial spines with three serrated edges, each of which bears one single large lateral branch, concavely curved towards the distal end. By-spines of the inner shell very numerous.
Dimensions.—Diameter of the outer shell 0.5, inner 0.17.
Habitat.—Central Pacific, Station 264, surface.
Definition.—Astrosphærida with two extracapsular cortical shells, connected by long prismatic, radial spines; outer shell with thin radial by-spines.
The genus Drymosphæra differs from its ancestral form Leptosphæra in the development of radial by-spines on the surface of the outer shell, the inner shell being smooth.
Definition.—Radial by-spines simple, not branched (main spines simple).
1. Drymosphæra hexagonalis, n. sp.
Inner shell with regular, hexagonal meshes and very thin thread-like bars; outer shell twice as broad, with simple triangular meshes and thin thread-like bars, which bear very numerous, bristle-shaped radial by-spines. Radial main spines with three smooth edges. (Differs from the first species of the other three genera of Diplosphærida in the presence of by-spines on the outer, and their absence on the inner shell.)
Dimensions.—Diameter of the outer shell 0.32, inner 0.16.
Habitat.—Central Pacific, Station 274, surface.
2. Drymosphæra polygonalis, n. sp. (Pl. 19, fig. 1).
Diplosphæra polygonalis, Haeckel, 1879, Atlas.
Inner shell with irregular, polygonal meshes and very thin thread-like bars; outer shell one and a half times as broad, with simple triangular meshes and thicker bars, which bear numerous bristle-shaped radial by-spines (in the figure the majority of these are broken off). Radial main spines with three smooth edges. (Similar to Leptosphæra polygonalis and Diplosphæra polygonalis, but differs from both in the presence of by-spines on the outer, and their absence on the inner shell.)
Dimensions.—Diameter of the outer shell 0.33, inner 0.22.
Habitat.—North Pacific, Station 236 south of Japan, surface.
Definition.—Radial by-spines forked or branched (main spines simple).
3. Drymosphæra furcata, n. sp.
Inner shell with irregular, polygonal meshes and thin bars, the former five times as broad as the latter; outer shell two and a half times as broad, with simple triangular meshes and smooth bars, bearing numerous long smooth bristle-shaped by-spines, which in the distal half are forked. Radial main spines with three smooth edges.
Dimensions.—Diameter of the outer shell 0.4, inner 0.16.
Habitat.—Indian Ocean, Ceylon, surface, Haeckel.
4. Drymosphæra cladophora, n. sp.
Inner shell with irregular, polygonal meshes, three to six times as broad as the smooth bars; outer shell twice as broad, with simple triangular meshes and very thin smooth bars, bearing numerous curved, irregularly branched, smooth by-spines. Radial main spines with three serrated edges.
Dimensions.—Diameter of the outer shell 0.4, inner 0.2.
Habitat.—Central Pacific, Station 276, surface.
5. Drymosphæra dendrophora, n. sp. (Pl. 20, figs. 1, 1a, 1b).
Inner shell with irregular, polygonal meshes and very thin thread-like bars; outer shell one and a half times as broad, with simple triangular meshes and thicker bars, which bear a forest of very numerous, repeatedly dichotomous or irregularly branched, curved by-spines, longer than the diameter of the outer shell. Radial main spines with three dentated edges. All parts of the skeleton, the net bars as well as the radial beams and spines, are very elegantly denticulated (fig. 1b). The central capsule (fig. 1a) completely distends the inner shell and forces out protuberances through all its pores; in its centre lies a nucleus one-third its size.
Dimensions.—Diameter of the outer shell 0.25, inner 0.16.
Habitat.—Central Pacific, Station 271, surface.
Definition.—Astrosphærida with two extracapsular cortical shells, connected by long, prismatic, radial spines; inner and outer shell with thin radial by-spines.
The genus Astrosphæra differs from its ancestral form, Leptosphæra, in the development of radial by-spines on the surface of both shells.
Definition.—Radial main spines simple without lateral branches.
1. Astrosphæra hexagonalis, n. sp. (Pl. 19, fig. 4).
Inner shell with regular, hexagonal meshes and very thin bars, having a bristle-shaped, short radial by-spine in each hexagon-corner; outer shell twice as broad, with simple triangular meshes and thicker bars, bearing one row of simple bristle-shaped, curved, radial by-spines. Radial main spines with three smooth edges.
Dimensions.—Diameter of the outer shell 0.32, inner 0.16.
Habitat.—South Pacific (West Patagonia), Station 302, surface.
2. Astrosphæra splendens, n. sp.
Inner shell with regular, hexagonal meshes, four times as broad as the bars, and covered with numerous curved, long, bristle-shaped by-spines; outer shell three times as broad, with simple triangular meshes and thin bars, bearing a row of very long, curved, bristle-shaped by-spines. Radial main spines with three dentated edges. All parts of the skeleton elegantly denticulated, as in Drymosphæra dendrophora (Pl. 20, fig. 1).
Dimensions.—Diameter of outer shell 0.7, inner 0.24.
Habitat.—Tropical Atlantic, Station 347, surface.