Plate 1

Fig. 1 The Colony X 3/5. Fan shaped, and flattened in the plane of branching.

Fig. 2 Longitudinal section of a polyp to show 3 distinct regions: Hypostome; glandular region; region of large endodermal cells.

Fig. 3 Cross section of a polyp in the hypostome region.

Fig. 4 The skeleton of a branch tip. Flattened, longitudinal fibres are joined by struts (transverse fibres).

co, coelenteron; ect, ectoderm; end, endoderm; gl, gland-cell region; hyp, hpostome; long fib, longitudinal fibre; trans fib, transverse fibre; t, tentacle.