Spines compressed quadrangular, with short, simple or bifid apex, pyramidal on the base, without leaf-cross. From the two broader edges of the proximal half arise two longitudinal rows of opposite apophyses; three to four slender teeth in each row.
Dimensions.—Length of the spines 0.2, breadth 0.08.
Habitat.—Mediterranean, Cette (French shore), surface, J. Müller.
4. Astrolonche pinnata, n. sp.
Spines in the distal half compressed, linear, two-edged, with bifid apex; in the proximal half three times as broad lanceolate, at the base pyramidal, without leaf-cross. From the two broader edges of the proximal half arise two longitudinal rows of opposite apophyses; four to six broad triangular teeth in each row.
Dimensions.—Length of the spines 0.3 to 0.4, breadth in the outer half 0.012, in the inner half 0.03 to 0.04.
Habitat.—South Atlantic, Station 332, surface.
Subgenus 2. Astrolonchidium, Haeckel.
Definition.—Each spine with three parallel double rows of opposite apophyses.
5. Astrolonche serrata, Haeckel.