Page:Scientific results HMS Challenger vol 18 part 1.djvu/517

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REPORT ON THE RADIOLARIA
309

Pl. 15, fig. 7), three times as broad as the bars; ten to twelve on the half equator. Medullary shell ellipsoidal (with longitudinal main axis), one-third as broad as the cortical shell.

Dimensions.—Major axis of the cortical shell 0.1, minor axis 0.08; pores 0.009, bars 0.003; axis of the medullary shell 0.03 and 0.025.

Habitat.—Mediterranean, Smyrna, Haeckel, surface.


5. Druppula areca, n. sp.

Cortical shell thin walled, with smooth surface and regular network; both its axes bear the proportion of 4 : 3. Pores regular, circular, four times as broad as the bars; fifteen to eighteen on the half equator. Medullary shell spherical, half as broad as the cortical shell.

Dimensions.—Major axis of the ellipsoidal cortical shell 0.12 to 0.14, minor axis 0.1 to 0.11; pores 0.008, bars 0.002; diameter of the medullary shell 0.05 to 0.06.

Habitat.—Indian Ocean, off Bombay, Haeckel.


6. Druppula ovata, Haeckel.

Haliomma ovatum, Ehrenberg, 1854, Mikrogeol., pl. xx. I. fig. 20. Haliomma ovatum, Haeckel, 1862, Monogr. d. Radiol., p. 432.

Cortical shell thin walled, with smooth surface and regular network; proportion of both axes = 3 : 2. Pores regular, circular, three times as broad as the bars; nine to ten on the half equator. Medullary shell spherical, one-third as broad as the cortical shell.

Dimensions.—Major axis 0.08 to 0.1, minor axis 0.05 to 0.06; pores 0.003, bars 0.001; diameter of the medullary shell 0.02.

Habitat.—Fossil in the Tertiary rocks of the Mediterranean coast, Greece (Zante), Ehrenberg; Sicily (Caltanisetta), Haeckel.


7. Druppula caryota, n. sp.

Cortical shell thick walled, with rough surface and regular network; proportion of both axes = 5 : 4. Pores regular, circular, twice as broad as the bars; sixteen to twenty on the half equator. Medullary shell ellipsoidal, one-third as large as the cortical shell.

Dimensions.—Major axis 0.2 to 0.22, minor 0.16 to 0.18, pores 0.008, bars 0.004; axes of the medullary shell 0.07 and 0.055.

Habitat.—Pacific, central area, Stations 266 to 268, depth 2700 to 2900 fathoms.


Subgenus 2. Druppulissa, Haeckel.

Definition.—Pores of the cortical shell irregular, of different form or size, usually subcircular or roundish, sometimes lobed or compound.