$82 63. Gastrid. 2.THALASSI0PHYTyE. PL cell aph. 
13. Gaslridium amphibium . Amphibious belly-weed * 
Thallus cylindrical, hairlike, twice or thrice pinnate; 
branches and twigs horizontal, alternate, uppermost lan- 
ceolate, rolled inwards at the tip. 
Fucoides erectum fruticuli specie, summitatibus inflexis, Dilten in Ran 
Syn. 38, 4. 
Fucus scorpioides, Iluds. FI. Angl. ed. 1, 471. 
Fucus amphibius, Huds. ed. 2, 590; I'urn. Hist. 101 ; Engl. Bot. 1428. 
Chondria amphibia, Agardh Disp. 18. 
Plocamium amphibium, Lamour. Thai. 
Sea-shores; perennial; summer. 
14. Gaslridium coccineum . Scarlet belly-iveed. 
Thallus compressed; branches many, irregular; twigs 
awlshape, pectinate, on one side. 
Miiscus marinus rubens pennatus, Raii Syit. ed. 2, 8. 
Fucus Plocamium, Gmelin. 16. 
Fucus coccineus, Huds. FI. Angl. 586. 
Fucus cartilagineus, (Eder Enuin. 2, 131. 
Ceramium Plocamium, Roth Cat. 3, 107. 
Plocamium vulgare, Lamour. Thai. 50. 
Delesseria coccinea, Agardh Lisp. 14. 
Plocamium coccineus, Lyngbye Hydr. Dan. 39. 
e. Rytiphlaea. Thallus thread shape ; branches 2-rowed ; 
twigs slightly jointed, incurved; tubercles lateral . 
15. Gaslridium pinastroides. Pinasterlike belly-weed . 
Thallus threadlike; branches numerous; tip rolled in- 
wards; twigs mostly simple, awlshape, scattered, facing 
one way. 
Fucus pinastroides, Gmelin, 127 ; I'urn. Hist. 11 ; Engl. Bot. 1042. 
Fucus incurvus, Huds. FI. Angl. 590. 
Ceramium incurvum, De Candolle FI. Gall . 2, 43. 
Rytipltsea pinastroides, Agardh Disp. 25. 
Cigartina pinastroides, Lyngbye Hart. 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. 
