348 47. Palmel. 2. THALASSIOPHYTZ. PI. cell. aph. 
XXII. 47. PALMELLA. Lyngbye. Tremlbler. 
Thallus cylindrical, simple or branched, solid; integu- 
~ ment membranaceous; inside gelatinous, cellular; sporzdia 
globular, immersed in the thallus.—Marine. 
1. Palmella defracta. Broken trembler. 
Thallus threadlike, simple, twisted, elastic, viscid, pel- 
lucid; sporidia globular, pale red. 
Ulva defracta, With, Bot. Arr. 4,124; Engl. Bot. 1626. 
On sea-plants. 
Thallus 2 to 12 inches long, 1-8th inch in diameter. 
2. Palmella elminthoides. Wormlike tremller. 
Thallus threadlike, mostly simple, opake, slippery, rather 
blunt; central line dark, parenchymatous; sporidia very 
minute, opake. 
Ulva elminthoides, With. Bot. Arr. 4, 141. 
Rocks in the sea; July. 
Thalli aggregated, 4 to 7 inches long, twisted. 
XXII. 48. MERRETTIA. Merrett. 
Thallus flat, diversely shaped, solid; integuments mem- 
branaceous; inside cellular, gelatinous; sporzdza scattered, 
immersed. 
1. Merrettia adnata. Adnate merrett. 
Thallus diversely shaped, gelatinous, wrinkled, brownish 
yellow; sporidia globular, brown. 
Tremella adnata, Hudson Fl. Angl. 555. 
Palmella adnata, Lyngbye Hydr. Dan. 205. 
On rocks between high and low water in the sea. 
Thallus wrinkled, 3 to 6 inches in diameter, less than a 
quarter thick. 
2. Merrettia coriacea. Leathery merrett. 
Thallus flat, adnate, very wide, indeterminate, smooth, 
slippery, dull red; sporzdia globular, 
Ulva rupestris, Engl. Bot. 2194. 
Upright faces of fells over which water trickles. 
‘Thallus 2 or 3 feet wide, resembles a spread-out piece of 
very wet reddish or greenish brown washed leather, but 1s 
not so tenacious; has been mistaken for flesh. 
