Seagrasses
Plants in intertidal or subtidal zones, with leaves arising from a root system, to 4 m/13 ft long, p. 45
Green Seaweeds
Seaweeds light to dark green, a “grass” green, p. 49
Filaments
Seaweeds thread-like or filamentous, less than 1 mm/0.04 in wide, p. 50
Identifying Pacific Seaweeds
Thumbnail Identification Guide | 35
Unbranched Filaments
Filament unbranched throughout, to 1 cm/0.4 in diameter, see Filaments, p. 51
Branched Filaments
Filament branches at least once, may be regular or irregular branching, to 1 cm/0.4 in diameter, see Filaments, p. 55
Blades
Seaweeds leaf-like, 2 mm–50 cm/0.08–20 in wide,p. 60
Cylinders
Seaweeds hollow tubes or cylinders, 2 mm–5 cm/ 0.08–2 in wide, 2 cm–50 cm/0.75–20 in long, p. 66
Spongy texture
Seaweeds spongy in texture, crusts and branched forms, to 50 cm/20 in in greatest dimension, p. 68
Unicellular forms
Seaweeds green dots, very small unicells in other seaweeds and animals, or in water causing pea soup-like appearance of tide pools, p. 70
red Seaweeds
Seaweeds yellowish to red to pink to purple, or, if hardened or calcareous, pink to purple, p. 74
Hard crusts (calcified)
Seaweeds crusts lacking upright portions, 2 mm–1 m/0.08 in–3 ft in diameter, p. 76
Pacific Seaweeds
36 | Thumbnail Identification Guide
Branched and hardened (calcified)
Seaweeds branched consisting of hardened seg-ments, to 30 cm/12 in long, p. 81
Soft crusts
Seaweeds soft crusts lacking upright portions, to 50 cm/20 in in diameter, p. 89
Parasitic seaweeds
Seaweeds parasitic on other red algae, weakly pigmented, less than 7 mm/0.25 in at greatest dimension, p. 93
Filaments
Seaweeds thread-like or filamentous, less than 1 mm/0.04 in wide, p. 96
Solid or hollow cylinders
Seaweeds cylindrical, may be sparsely branched, 2 mm–3 cm/0.08–1.2 in wide, to 20 cm/8 in long, p. 106
Blades with regular bumps
Seaweeds bladed with pronounced bumps, no or little branching, to 1 m/3 ft long, p. 109
Blades with ribs and veins
Seaweeds bladed with conspicuous ribs, often branched, to 40 cm/16 in long, p. 114
Simple blades
Seaweeds bladed and simple, not repeatedly branched, to 1 m/3 ft long, p. 121
Branched in one plane, flattened
Seaweeds repeatedly branched mostly in one plane, flattened, to 40 cm/16 in long, p. 131
Bushy branched
Seaweeds repeatedly branched in all dimensions, bushy, to 50 cm/20 in long, p. 145