Page:Scientific results HMS Challenger vol 18 part 2.djvu/872

1748 latter (with the terminal coronets), and the anchor pencils, covering the surface of the thicket and the mantle, seem to project over the surface of the calymma. The entire form of the latter is therefore a symmetrical polyhedron. The phæodium fills up a small part only of the calymma, and is usually enclosed in the two galeæ and their rhinocannæ (Pl. 127, figs. 5, 9), but often also a part of the phæodium is scattered around the oral half of the central capsule.

Definition.— with two paired lateral frenula on each galea, and with free terminal branches on the hollow radial tubes, without an external lattice-mantle. Eight to sixteen long styles are prominent over the surface of the fork-thicket, which is composed of the caudal brush and the dichotomous basal branches of the styles.

Definition.— with two paired lateral frenula on each galea, without external lattice-mantle, armed with eight styles (two pairs of styles on each valve).