Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, Second Part: Subclass Osculosa; Index / Report on the Scientific Results of the Voyage of H.M.S. Challenger During the Years 1873-76, Vol. XVIII

by Ernst Haeckel

Habitat.—Central Pacific, Station 274, depth 2750 fathoms.

Genus 510. Archibursa,[^[127]] Haeckel, 1881, Prodromus, p. 429.

Definition.—Archiperida (vel Monocyrtida triradiata clausa) without internal columella and without apical horn.

The genus Archibursa has probably arisen from Peridium by loss of the apical horn, and is the only genus of Archiperida which bears no horn. The three basal feet are well-developed. It differs from the similar Tristylospyris by the absence of the sagittal ring and the corresponding longitudinal constriction.

1. Archibursa tripodiscus, n. sp. (Pl. [98], fig. 6).

Shell subspherical, smooth, with irregular roundish pores. Basal plate with three large triangular pores of equal size (fig. 6). Three feet widely divergent, straight, three-sided prismatic, about as long as the diameter of the shell.

Dimensions.—Diameter of the shell 0.07, length of the feet 0.09.

Habitat.—Central Pacific, Station 272, depth 2600 fathoms.

Family LX. Phænocalpida, n. fam.

Archiphormida et Archiphænida, Haeckel, 1881, Prodromus, pp. 428, 429.