Page:Scientific results HMS Challenger vol 18 part 1.djvu/1050

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Definition.—Condyles of the neighbouring plates grown together and sutures obliterated, therefore the whole shell forms a single piece of acanthin.

11. Lychnaspis echinoides, Haeckel.

Haliomma echinoides, J. Müller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p.36, Taf. v. figs. 3, 4.

Haliommatidium echinoides, J. Müller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 22.

Haliommatidium echinoides, Haeckel, 1862, Monogr. d. Radiol., p. 422.

Parmal meshes pentagonal or somewhat roundish, four times as broad as the bars, and of about the same size as the polygonal meshes. By-spines (about two hundred) short, zigzag. Radial spines thin; their outer conical part shorter than the inner cylindrical part. Sutures perfectly obliterated, but recognisable by the characteristic pair of divergent by-spines. (Some recent observations on this species, made during 1880 in Portofino, have convinced me that the interpretation of it given in my Monograph, 1862, loc. cit., was quite correct.)

Haliomma ligurinum, J. Müller (= Haliommatidium ligurinum, Haeckel, L. N. 16, p. 423) seems to be closely allied to the preceding.

Dimensions.—Diameter of the shell 0.12 to 0.14, parmal pores 0.015, sutural pores 0.01 to 0.02, bars 0.004.

Habitat.—Mediterranean, Nice, Saint Tropez (J. Müller); Portofino near Genoa (Haeckel).

12. Lychnaspis haliommidium, n. sp.

Lychnaspidium haliommidium, Haeckel, 1882, Manuscript.

Parmal meshes circular, twice as broad as the bars, smaller than the irregular sutural meshes. By-spines (about two hundred) barbed and zigzag, as long as the radius. Radial main-spines four-sided; their outer pyramidal part shorter than the inner prismatic part. Sutures perfectly obliterated.

Dimensions.—Diameter of the shell 0.1, parmal pores 0.01, sutural meshes 0.015 to 0.02.

Habitat.—South Atlantic, Station 335, depth 1425 fathoms.

13. Lychnaspis rabbeana, n. sp.

Parmal meshes circular, very small, of the same breadth as the bars, and much smaller than the irregular sutural meshes. By-spines (about one hundred) very long and thin, zigzag, about as long as the diameter of the shell. Radial main-spines cylindrical, thick, twice to three times as long as the diameter of the shell. Sutures perfectly obliterated, with thickened condyles. Named in honour of Captain Henrik Rabbe (of Bremen), to whom I am indebted for many new Indian and Atlantic Radiolaria.

Dimensions.—Diameter of the shell 0.086, parmal pores 0.002, sutural pores 0.012, bars 0.002.

Habitat.—Indian Ocean (Madagascar), Rabbe, surface.