4. Tholartus tripanis, n. sp.
Central chamber of the same size as both cupolas. Surface of the shell thorny, everywhere covered with short conical radial spines, about as long as the cupolas. Pores regular or subregular, circular, twice as broad as the bars; eight to ten on the half meridian.
Dimensions.—Length of the shell 0.1, breadth 0.12; pores 0.01, bars 0.005.
Habitat.—South Pacific, Station 295, surface.
5. Tholartus sagitta, n. sp.
Central chamber twice as large as both cupolas. Surface of the shell spiny, with eight to twelve regularly (?) distributed radial spines, radiating from the two constrictions between the three chambers. Spines needle-shaped, very thin and long. Pores subregular or irregular, roundish or circular, about three times as broad as the bars; twelve to sixteen on the half meridian.
Dimensions.—Length of the shell 0.11, breadth 0.15; pores 0.01, bars 0.003.
Habitat.—North Pacific, Station 244, surface.
Genus 290. Tholodes,[[329]] n. gen.
Definition.—Tholonida with double cortical shell (with external veil), with two hemispherical cupolas, opposite on the poles of one axis; central chamber between them simple (without medullary shell).