203 



Phyc.); De Toni Syll. Alg. I, p. $i6.-H. obala Kuetz. Tab. Phyc., 

 tab. 25, f. i ; J. Ag. Till Alg. Syst. VIII, p. 86 ; De Toni Syll. Alg. I, 

 p. 523.^. vcrsatilis }. Ag. Till Alg. Syst. VIII, p. 86; De Toni 

 Syll. Alg. I, p. 524. II. macroloba Harv. Phyc. Aust. t. 267 et 

 descript. pro part.; Asken. Gazelle, Th. IV, Bot. Alg., p. 14, 

 tab. Ill, f. 6, 8. 9, 10, tab. IV, f. u. H. Tuna (non Lam.) Okam., 

 [S] M n ^IK 1 %> US P- 1 86. H. papyracca (non Zan.) Okam., [55] 

 WIRI.L p- 187. 



Plants varying in length to about 7-15 cm., slightly incrusted 

 with lime, branching in one plane di-, tri- or polychotomously. 

 Root short, more or less bulbous. Joints sessile, varying from 

 broadly cuneate, pyriform, oval to discoid and re.niform, not-ribbed, 

 margin entire, flat ; varying in size to about 20 mm. long, 25 mm. 

 broad, and 0.5-1 mm. thick. Apex of joint sometimes slightly raised, 

 giving the appearence of a cushion at. the base of the node. Filaments 

 of central strand fuse in twos or threes at the apex of each joint. 

 Peripheral cells irregularly polygonal in surface-view ; 30-48 p across 

 about 40-120 n long. Side walls of adjacent cells of peripheral 

 layer are in contact for j- 1 , their length. Colour light green. 



Hab. : On rocks below low tide (Hamajima) extending to 44 

 fath. (Ogasawara Is!.). Ryukyu, Amami-Oshima and Tanegashima, 

 Ogasawara Isl. (22-44 fath.), Goto Isl., Nomo Zaki, Kayaki and 

 Takahama (14 fath., near Nagasaki), Hamajima (Prov. Shima). 



The existence of this plant at Hamajima, Prov. Shima, is the 

 hitherto-known northernmost limit of the distribution of the species 

 of Halimeda in the north Pacific. 



PI. CXLVII. Fig. 1 : frond of Halimeda cuneata Hering. 

 bearing discoid joints (Ryukyu), \. Fig. 2 : portion of another 



