175 



i-4 mm broad for the most part, 0.5-1 mm broad in the ultimate 

 pinnellae, 2-3 times pinnately branched in disticho-alternate manner. 

 Branches almost linear, often narrowed toward the base, or little 

 broader upward, patent, standing on the angle of almost 45, 

 roundish or lobed at apices. Outline of branches is pyramidal, 

 lower branches being the longest. Pinnellae simple, linear or 

 linear-clavate, truncated or expanded toward apex, often much 

 lobed.r Tetraspores aggregated at the apical portion of pinnellae 

 which do not change their form. Cystocarps ovato-urceolate with 

 wide ostiole, sitting at the side of pinnulae. Colour dark purplish, 

 often fading to greenish-yellow. Substance fleshy, soon becoming 

 soft; the plant pretty well adheres to paper in drying. 



Hab. : On rocks below low-tide. Common along the Pacific 

 side from Ryukyu to Hakodate, and the Japan Sea. 



PL. CXCII. Fig. 1-3 : different forms of the frond of Lau- 

 rencia pinnatifida (Gm.) Lamour., -f-. Fig. 4 : cross-section of 

 branch, -f-. Fig. 5 : portion of branch magd., -f-. Fig. 6 : branch 

 bearing tetraspores, -f-. Fig. 7 : tetraspores seeft through the 

 surface of frond, ^fo. Fig. 8: tetraspores, sae. Fig. 9 : cysto- 

 carps, -\ Q . Fig. 10 : vertical section of a cystocarp, \ a . 



Laurencia obtusa (Huds.) Lamour. 



Nom. Jap.I udtsudesozo. 



PL. CXCIII. 



Laurencia obtusa (Huds). Lamour. Essai, p. 42 ; J. Ag. Sp. 

 Alg. II, p. 750 ; Id. Epicr. p. 653 ; Harv. Phyc. Brit. t. 148 ; Kiitz. 

 Sp. Alg. p. 854; Id. Tab. Phyc. XV, t. 54-55 ; De Toni Syll. Alg. 

 IV, p. 791; Hauck Meeresalg. p. 206. Fitcus obtusus Turn. Hist. 

 Fuci t. 21. Okam. Synop., B#H^lt (2nd. ed.) p. 69. 



Fronds often forming somewhat intricated mass, cylindrical, 



