Subgenus 2. Amphirrhopella, Haeckel.
Definition.—Both opposite arms of similar size and form, with terminal spines.
3. Amphirrhopalum bigeminum, n. sp.
Both arms equal, in the proximal larger half simple, in the distal smaller half forked; each branch triangular, with a strong conical terminal spine. Axis of the branches straight. (Resembles Dicranastrum cornutum, Pl. [45], fig. 2, but without lateral arms.)
Dimensions.—Radius of the arms (without spines) 0.15, basal breadth 0.03; breadth of the bifurcation 0.08.
Habitat.—South Pacific, Station 284, surface.
4. Amphirrhopalum echinatum, n. sp. (Pl. [45], fig. 10).
Both arms equal, in the proximal smaller half simple, nearly square, in the distal larger half forked; the branches thorny, armed at the end with numerous spines, one larger on the terminal pole of the concavely curved arm-axis.
Dimensions.—Radius of the arms (without spines) 0.15, basal breadth 0.05; breadth of branches 0.03.
Habitat.—Pacific, central area, Station 266, depth 2750 fathoms.