Page:Scientific results HMS Challenger vol 18 part 2.djvu/298

1174 2. Phænocalpis ocellata, Haeckel.

Petalospyris ocellata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xxii. fig. 9.

Shell subspherical, smooth, with irregular roundish pores, about as broad as the bars. Columella slightly curved and excentric, prolonged into a slender conical horn of the same length. Six basal feet similar to the horn, slightly divergent.

Dimensions.—Shell 0.06 long, 0.07 broad; horn and feet 0.05 long.

Habitat.—Fossil in Barbados.

3. Phænocalpis carinata, Haeckel.

Petalospyris carinata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xxii. fig. 6.

Shell campanulate, rough, with irregular roundish pores, smaller than the bars. Columella straight, central, prolonged into a stout conical horn of the same length. Nine basal feet slender, triangular, longer than the shell, nearly vertical, with a middle rib in the basal half.

Dimensions.—Shell 0.05 long, 0.06 broad; horn 0.04 long, feet 0.08 long.

Habitat.—Fossil in Barbados.

4. Phænocalpis flabellum, Haeckel.

Petalospyris flabellum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, Taf. xxii. fig. 7.

Shell campanulate smooth, with very small circular pores, half as broad as the bars. Columella straight, central, prolonged into a pyramidal horn of half the length. Twelve to fifteen basal feet lamellar, linear, twice to three times as long as the shell, parallel and vertical, pointed at the distal end.

Dimensions.—Shell 0.04 long, 0.05 broad; horn 0.02 long, feet 0.1 to 0.12 long.

Habitat.—Fossil in Barbados.

Definition.— (vel Monocyrtida multiradiata clausa) with an internal axial branched columella, prolonged outside into an apical horn.

The genus Phænoscenium differs from the preceding Phænocalpis in the branched columella, which is connected by three or six ascending branches with the inner wall of the shell. It bears therefore to the latter the same relation that Cladoscenium exhibits to Euscenium. The former genera may have been derived from the latter by interpolation of new interradial feet between the three primary perradial feet.