The figures in the following plates are all in :iatural size of the fronds. 



Plate IV. 



Fig. 1. Amphiroa valonioides. 



Fig. 2. Amphiroa cretacea, Endl. 



Fig. 8. Amphiroa cretacea, Endl. f. rosariformis. 



Fig. 4. Amphiroa rigida, Lamx. 



Figs. 5 — 6. Amphiroa ephedrœa, Lamh. ß. 



Figs. 7 — 8. Amphiroa ephedrœa, Laml'. y. 



Fig. 9. Amphiroa zonata. 



Fig. 10. Amphiroa echigoensis. 



Figs. 11 — 13. Amphiroa 2>usilla. 



11. Decumbent frond from the ventral side, conceptacles are seen frosting 



on this side. 



12. do. from the dorsal side. 



13. A frond in vertical habit ; the conceptacles are seen on both sides. 



Figs. 14 — 15. Amphiroa canaliculata, Mart. 

 View from the dorsal side : conceptacles are seen frosting on this side. 

 15. View from the ventral side : two canals are seen running along the 

 edges of the articuli. 



