1. Castanella wyvillei, n. sp. (Pl. 113, fig. 6).
Pores regular, circular, of equal size, hexagonally framed, of the same breadth as the bars. Radial bristles twice as long as the diameter of one pore. Mouth with five to six parallel, conical strong teeth, which are twice as long as a bristle (fig. 6a).
Dimensions.—Diameter of the shell 0.5 to 0.7, of the pores 0.02 to 0.03.
Habitat.—North Pacific, Stations 252 to 256, surface.
2. Castanella thomsoni, n. sp.
Pores regular, circular, of equal size, hexagonally framed, twice as broad as the bars. Radial bristles about as long as the diameter of one pore. Mouth with four strong, conical teeth, forming a regular cross, four times as long as a bristle.
Dimensions.—Diameter of the shell 0.7 to 0.8, of the pores 0.03.
Habitat.—South Pacific, Stations 295 to 298, surface.
3. Castanella campbelli, n. sp.
Pores regular, circular, hexagonally framed, three times as broad as the bars. Radial bristles half as long as the radius of the shell. Mouth with a coronet of eight conical, parallel teeth, of the same length as the bristles, but four to six times as thick.
Dimensions.—Diameter of the shell 0.4 to 0.45, of the pores 0.025.
Habitat.—Central Pacific, Stations 270 to 274, surface.
4. Castanella sloggetti, n. sp.
Pores subregular, circular, without frames, of different sizes, about twice as broad as the bars. Radial bristles three times as long as one pore. Mouth with five or six strong, conical teeth, twice as long as the bristles.
Dimensions.—Diameter of the shell 0.3 to 0.36, of the pores 0.02 to 0.03.
Habitat.—Tropical Atlantic, Stations 347 to 349, surface.
5. Castanella balfouri, n. sp.
Pores irregular, roundish, two to three times as broad as the bars. Bristles about one-fourth as long as the radius. Mouth with four strong conical teeth, forming a cross, somewhat longer and much thicker than the bristles.
Dimensions.—Diameter of the shell 0.22 to 0.28, of the pores 0.01 to 0.02.
Habitat.—North Pacific, Stations 240 to 245, surface.
