Page:Scientific results HMS Challenger vol 18 part 1.djvu/992

784 sword-shaped, only two-thirds or one-half as long, and one-third or one-fourth as broad, each with two opposite teeth in the distal part. Central capsule ellipsoidal.

Dimensions.—Length of the two major spines 0.13, breadth 0.02; length of the eighteen minor spines 0.1.

Habitat.—North Atlantic, Station 352, surface.

4. Amphilonche tenuis, Haeckel.

Amphilonche tenuis, Haeckel, 1862, Monogr. d. Radiol., p. 389, Taf. xvi. fig. 1, Taf. xviii. fig. 16.

Acanthometra tenuis, Haeckel, 1860, Monatsber. d. k. Akad. d. Wiss. Berlin, p. 807.

Two principal spines quadrangular prismatic, with smooth edges, slightly or not at all prominent, of equal breadth throughout their whole length; apex simple or bifid; base a small pyramid, without leaf-cross. Eighteen smaller spines of the same form, but only one-fourth or one-third as long. Central capsule spherical or ellipsoidal, colourless.

Dimensions.—Length of the two major spines 0.2 to 0.3, of the eighteen minor spines 0.05 to 0.1.

Habitat.—Mediterranean (Messina); Atlantic, Station 354, Canary Islands, surface.

5. Amphilonche denticulata, Haeckel.

Amphilonche denticulata, Haeckel, 1862, Monogr. d. Radiol., p. 390, Taf. xvi. fig. 2, Taf. xviii. fig. 17.

Two principal spines quadrangular prismatic, with prominent, elegantly denticulated edges, of equal breadth throughout their whole length; apex simple or truncated; base a small pyramid, without leaf-cross. Eighteen smaller spines of the same form, but only one-fourth or one-third as long. Central capsule ellipsoidal, opaque, yellowish-brown.

Dimensions.—Length of the two major spines 0.3 to 0.4, of the eighteen minor 0.1; breadth of the former 0.009, of the latter 0.006.

Habitat.—Mediterranean (Messina), Haeckel, surface.

6. Amphilonche heteracantha, Haeckel.

Amphilonche heteracantha, Haeckel, 1862, Monogr. d. Radiol., p. 293, Taf. xvi. fig. 7.

Acanthometra heteracantha, Haeckel, 1860, Monatsber. d. k. Akad. d. Wiss. Berlin, p. 808.

Two principal spines quadrangular prismatic, very large, with four broad, prominent, lamellar edges, of equal breadth throughout their whole length. Apex as well as the base a four-sided pyramid. Eighteen smaller spines very thin, conical, with bristle-shaped apex; base a small pyramid, without leaf-cross. Central capsule cylindrical or violin-shaped, opaque yellow.

Dimensions.—Length of the two major spines 0.2 to 0.3, breadth 0.015 to 0.02; length of the eighteen minor spines 0.1 to 0.15, basal breadth 0.004 to 0.008.

Habitat.—Mediterranean (Messina); Central Pacific, Station 271, surface.