$82 63. Gastrid. 2. THALASSIOPHYT. Pl. cell. aph. 
13. Gastridium amphibium. Amphibious belly-weed. 
Thallus cylindrical, hairlike, twice or thrice pinnate ; 
branches and iwigs horizontal, alternate, ere lan- 
ceolate, rolled inwards at the tip. 
Fucoides erectum fruticuli specie, summitatibus inflexis, Dillen in Raii 
Syn. 38, 4. 
Fucus scorpioides, Huds, Fl. Angl. ed. 1, 471. 
Fucus amphibius, Huds, ed. 2,590; Turn. Hist.101; Engl. Bot. 1428, 
Chondria amphibia, Agardh Disp. 18. 
Plocamium amphibium, Lamour. Thal. 
‘Sea-shores; perennial; summer. 
14. Gastridium coccineum. Scarlet belly-weed. 
Thallus compressed ; branches many, irregular; twigs 
awlshape, pectinate, on one side. 
Muscus marinus rubens pennatus, Rati Syn. ed, 2, 8. 
Fucus Piocamium, Gmelin. 16. 
Fucus coccineus, Huds. Fl. Angl. 586. 
Fucus cartilagineus, @der Enum. 2, 131. 
Ceramium Plocamium, oth Cat. 3, 107. 
Plocamium vulgare, Lamour. Thal. 50. 
Delesseria coccinea, Agardh Disp. 14. ts 
Plocamium coccineus, Lyngbye Hydr. Dan. 39. 
e. Rytiphlea. Thallus threadshape ; branches 2-rowed ; 
twigs slightly jointed, incurved ; tubercles lateral. 
15. Gastridium pinastroides. Pinasterlike belly-weed. 
Thallus threadlike; branches numerous; tip rolled in- 
wards; éwigs mostly simple, awlshape, scattered, facing 
one way. 
Fucus pinastroides, Gmelin, 127; Turn. Hist. 11; Engl. Bot. 1042, 
Fucus incurvus, Huds. Fl. Angl. 590. 
Ceramium incurvum, De Candolle Fl. Gall. 2, 43. 
Rytiphea pinastroides, Agardh Disp. 25. 
Gigartina pinastroides, Lyngbye Hort. Dan, 45, 
Sea-shores; annual; summer. 
Thallus 3 to 6 inches high, naked below; twigs very 
dense, tiledlike. 
f. Ptilota. Thallus cartilaginous, compressed, pinnate ; 
sporidia in a globe surrounded with bristlelike involucra. 
16. Gastridium plumosum. Feathery belly-weed. 
Thallus much and irregularly branched ; . branches pin- 
nate; segments opposite, pectinate. 
