Page:Scientific results HMS Challenger vol 18 part 2.djvu/701

Rh ends are either simply pointed or bear a terminal spathilla, or a little crown of recurved teeth. According to these differences we may dispose the twenty-six species described into four subgenera.

Definition.—Terminal branches of the radial tubes simple, smooth, without lateral teeth and terminal spathillæ. Tubes usually thin and fragile.

1. Aulographis pandora, n. sp. (Pl. 103, figs. 2-9).

Radial tubes cylindrical, slender, straight or slightly curved, of equal breadth. Terminal branches of the tubes very variable in size and number (two to six, usually three or four), without lateral teeth and terminal spathillæ, slender, conical, slightly curved, directed outwards, twice to four times (rarely five to eight times) as long as the breadth of the tubes. This species is extraordinarily variable in the number and size of the simple terminal branches; the eight tubes, shown in figs. 2 to 9, are all found in one and the same specimen.

Dimensions.—Length of the tubes 0.5 to 1.5, breadth 0.01 to 0.03; branches 0.02 to 0.12.

Habitat.—Cosmopolitan; Mediterranean, Atlantic, Indian, Pacific; surface and in various depths.

2. Aulographis bovicornis, n. sp. (Pl. 103, figs. 12-14).

Radial tubes cylindrical, slender, straight, of equal breadth. Terminal branches usually two (rarely three), smooth, without lateral teeth and terminal spathillæ, eight to ten times as long as the breadth of the tube, pointed, S-shaped, or curved like the horns of an ox.

Dimensions.—Length of the tubes 0.6 to 0.8, breadth 0.015 to 0.02; branches 0.1 to 0.2.

Habitat.—South Atlantic (east of Buenos Ayres), Stations 323 to 325, surface.

3. Aulographis taumorpha, n. sp. (Pl. 103, fig. 16).

Radial tubes cylindrical, slender, straight, gradually tapering towards the pointed proximal end. Terminal branches constantly two, opposite in a tangential, slightly concave or nearly straight line, ten to twelve times as long as the breadth of the tube, smooth, straight in the proximal part, recurved in the distal part.

Dimensions.—Length of the tubes 0.7 to 0.8, breadth 0.01 to 0.015; branches 0.1 to 0.15.

Habitat.—North Pacific, Station 231, depth 2250 fathoms.