208 



Fronds often forming an irregular mass (3-4 cm. high, 4-5 

 cm. broad), much branched and in more than one plane; joints 

 rounded or reniform, prolonged below into two well marked 

 auricles, which overlap the lower joint, more or less flat, deeply 

 calcified, sessile, crenulated at margin and indistinctly elevated like 

 ribs ; size of joints varying to about 3-4 mm. long, 7-8 mm 

 broad. 



Hab. : Ishigaki Isl. (Ryukyu, Kuroiwa). 



/. ReilSChii Barton. PL. CXLVIII, Fig. 8-12. 

 Nom, Jap. ! Himc-sabotengnsa. 



//. Opuntia Lam. f. Rcnsckii Barton 1. c. p. 21, f. 22 and 

 iia. //. Rcnschii Hauck Ueber einige von J. M. Hildebrandt im 

 Eothen Meere u. Ind. Ocean gesammelte Algen (Hedwigia Heft. 

 V, 1886, p. 167 et Notarisia 1886, p. 254); DC Ton! Syll. Alg. 

 I, p. 525. //. gracilis (non Harv.) Okam., [KJ fa, H # & & % f m 

 p. 187. 



Fronds forming compact semicircular tuft, branches radiating 

 from the base, 4-7 cm. high. Lower joints of branches and fronds 

 obovate or cuneate, upper ones thin, small, irregularly round or 

 transversely ovate, indistinctly ribbed, usually 3-5 mm. broad, 2-4 

 mm. long, but in tho frond bearing larger and more roundish 

 joints, 7 mm. broad, 5 mm. long. Colour whitish or grayish- 



green. 



Hab. : Ryukyu (Kuroiwa), Kotosho (Taiwan, Kawakami). 



PI. CXLVIII. Fig. ]. : Halimcda Opuntia Lain. f. cordata 

 Barton, \. Fig. 2 : portion of the same, J. Fig. 3-4 : filaments 

 of central strand, showing mode of fusion; 3: H : ' ; 4: ' J ^. Fig. 

 5: surface view of peripheral cells, 1 { s -. Fig. 6-7: longitudinal 



