1. _Delesseria sanguinea_ The Crimson Delesseria 45 2. _Punctaria latifolia_ The Broad-leaved Punctaria 45 3. _Chordaria flagelliformis_ The Whip-like Chordaria 45 4. _Vaucheria submarina_ The Submarine Vaucheria 45 5. _Hildenbrandtia rubra_ The Red Hildenbrandtia 45 PLATE II. SEA-WEEDS. 1. _Bangia fusco-purpurea_ The Dark-purple Bangia 46 2. _Codium tomentosum_ The Closely-haired Codium 46 3. _Bryopsis plumosa_ The Feathery Bryopsis 41, 46 4. _Callithamnion arbuscula_ The Tree-like Callithamnion 46 5. _Leathesia Berkleyi_ Berkley’s Leathesia 46 6. _Laminaria phyllitis_ The Leafy Laminaria 46 PLATE III. 1. _Porphyra vulgaris_ The Common Porphyra 46 2. _Dumantia filiformis_ The Slender Dumantia 46 3. _Asperococcus Turneri_ Turner’s Asperococcus 47 4. _Rytiphlæa pinastris_ The Pine-like Rytiphlæa 47 5. _Chrysymenia rosea_ The Rose-coloured Chrysymenia 47 6. _Peyssonetia Dubyi_ Duby’s Peyssonetia 47 7. _Chordaria divaricata_ The Minutely-branching Chordaria 47 8. _Ectocarpus siliculosus_ The Podded Ectocarpus 46 9. _Nemaleon multifida_ The Many-cleft Nemaleon 46 10. _Nytophyllum punctatum_ The Spotted Nytophyllum 46 PLATE IV. SEA-WEEDS. 1. _Chondrus crispus_ The Curly Chondrus 41, 47 2. _Gigartina acicularis_ The Needle-shaped or Pointed Gigartina 47 3. _Ceramium strictum_ The Pink Ceramium 47 4. _Zonaria atomaria_ The Speckled Zonaria 47 5. _Plocamium coccineum_ The Scarlet Plocamium 47 PLATE V. SEA-WEEDS. 1. _Laurencia pinnatifolia_ The Pinnate-leaved Laurencia 42, 48 2. _Polysphonia parasitica_ The Parasitic Polysphonia 48 3. _Ulva latissima_ The Broad-leaved Ulva 48 4. _Rhodymenia lacinata_ The Lace-edged Rhodymenia 42, 48 5. _Gracilaria confervoides_ The Sponge-like Gracilaria 49 6. _Codium bursa_ The Purse-like Codium 49 7. _Iridæa edulis_ The Eatable Iridea 48 8. _Zonaria parvula_ The Lesser Zonaria 48 9. _Ectocarpus tomentosus_ The Hairy Ectocarpus 49 10. _Corallina officinalis_ The Common Corallina 49