English: Plate 5.
Fig. 1. Gelidium pusillum v. cylindricum. A small portion of a clump, mostly in the tetrasporangial state. The fertile portions appear slightly more swollen in the reproduction than in the fresh state, x 4.4. Ecuador.

Figs. 2-6. Gelidium galapagense. Fig. 2, a portion of a clump showing the rhizomatous portion and the erect branches with much-divided blades, which show tetrasporangial sori in the lobes. Fig. 3, a branch system with less-divided blades and larger sori. Figs. 4-6, a branch system of various degrees of simplicity, x 3.3. I. Isabela.
Fig. 7. Gelidium pusillum v. pacificum. A small portion of a tuft showing the basal and upper branches, the latter pinnately divided. The tetrasporangial sori appear in the tips of three branches, and the tip of one is indented owing to the disintegration of a matured sorus. x 3.0. I. Santa Maria.
Figs. 8-12. Gelidium isabelae. Portions of several branch systems to show the rhizomatous portions and the erect simple or subsimple blades. In fig. 12 one blade shows a tetrasporangial sorus. x 4.8. I. Isabela.

Fig. 13. Gelidium sclerophyllum. A portion of an unusually regularly pinnate axis, showing the lateral tetrasporangial branchlets with the sori in the tips surrounded by thickened sterile margins. One tip is perforated by the disintegration of a matured sorus. x 8.0. Ecuador.