Genus 522. Phænocalpis,[[139]] n. gen.
Definition.—Archiperida (vel Monocyrtida multiradiata clausa) with an internal axial simple columella, prolonged outside into an apical horn.
The genus Phænocalpis and the following Phænoscenium comprise those Archiphænida in which the vertical axis of the shell-cavity is occupied by a simple or branched columella, arising from the centre of the base and prolonged into an apical horn. This columella may be either the vertical rod of a Plectaniscus or the remnant of an original ring of Petalospyris. The latter genus differs by its sagittal constriction.
1. Phænocalpis petalospyris, n. sp. (Pl. [97], fig. 4).
Shell subspherical, rough, with irregular, roundish pores, larger than the bars. Columella straight, central, thin, prolonged into a large apical horn with three dentate edges. Six basal feet curved, divergent, lamellar, with a middle rib and dentate edges.
Dimensions.—Shell 0.07 long, 0.05 broad; horn and feet 0.06 long.
Habitat.—Tropical Atlantic, Station 347, depth 2250 fathoms.
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.