160 GRATELOUPIACEAE 
Halymenia Floresia (Clem.) Ag., from which, however, it differs 
manifestly in the thinner, more delicate, more “ulvoid,” rugose- | | 
scrobiculate, and apparently erose-lacerate rather than pinnately | 
branched thallus, the more distinctly filamentous cortex, the more 
patent dichotomies (or trichotomies) of the corticating filaments, 
and the commonly more obtuse surface cells. : 
The specimens, as they come to us, are of an olive-green color, | 
but it is probable that the natural color has been modified by the 
preserving fluid. 
Halymenia doryophora Mont. (Fl. Boliv.21. 18 39) is discussed 
under Grateloupia (p. 169). 4 
Halymenia lapathifolia Kütz. (Tab. Phyc. 16: 35. pl. 00. 1866) B 
is a Sebdenia (p. 162). | 
Halymenia limensis (Sond.) Kütz. (Tab. Phyc. 16: 34. pl. 07. 
1866) is described below under Sebdenia. 
SEBDENIA Berthold, Mitt. Zool. Sta. Neapel 3: 530. 1882; 
Cryptonem. Golf. Neapel 13, 21. 1884 
Sebdenia limensis (Sond.) comb. nov. 
Euhymenia limensis Sond.; Kiitz. Sp. Alg. 743. 1849. 
Halymenia limensis Kiitz. Tab. Phyc. 16: 34. pl. 07. 1866. 
Sarcodia (?) limensis De-Toni, Syll. Alg. 4: 416. 1900. | 
Thallus palmatifid-orbicular, about 12-15 cm. high, 10-17 cm. 
broad, froma subcuneate, more or less stipitate base, membranous, | 
slightly gelatinous, thin, mostly 40-100 и thick in sterile parts, 
becoming 150-225 и thick towards base, here and there at margins, 
dre; medulla mostly rather compact and firm, occasionally 
(especially : 
ау 4-8 u in diameter with frequent enlargements 8-15 # in 
