Definition.—All twenty spines provided with transverse apophyses.
3. Quadrilonche mesostaura, n. sp. (Pl. [131], fig. 1).
Four equatorial spines almost of the some form and length as the sixteen others, but of double or triple the breadth; each spine in its middle third with two opposite broad triangular apophyses, in the basal third rectangular, compressed, in the distal third isosceles triangular, with simple apex.
Dimensions.—Length of the four major spines 0.16, breadth 0.01 to 0.015; length of the sixteen minor spines 0.12, breadth 0.005.
Habitat.—Tropical Atlantic, Station 345, surface.
4. Quadrilonche telostaura, n. sp.
Four equatorial spines one and a half times as long and three times as broad as the sixteen others; all twenty spines cylindrical, of equal breadth throughout their whole length, with simple conical apex; each spine crossed in the distal third by two opposite, simple, conical apophyses.
Dimensions.—Length of the four major spines 0.3, breadth 0.012; length of the sixteen minor spines 0.2, breadth 0.004.
Habitat.—South Atlantic, Station 325, surface.