50 



Pterocladia capillacea (Gmel.) Born, et Thur. 



Norn. Jap. : Oba-kusa. 

 PL. CXV. 



Pterocladia capillacea (Gmel.) Born, et Thur. Not. Algol, p. 

 57, t. 20, f. 7-7, De Toni Syll. Alg. IV, p. 162. Gclidium capil- 

 laceum Kuetz. Tab. Phyc. XVIII, t. 53, Hauck Meeresalg. p. 190, 

 fig. 82 ac. Fncus capillaccus Gmel. Hist. Fuci p. 146, t. 15, f. i. 

 Gelidium corneum var. a. J. Ag. Sp. II, p. 470. Gelidium 

 (orncum var, pinnatnm Kuetz. Sp. p. 764, Tab. Phyc. XVII, t. 50, 

 f. d-f., Harv. Phyc. Brit. tab. 53, f. i. 



Fronds ancipito-compressed or almost flat, rising from fibrous 

 roots, linear, regularly 3-4 times pinnate, rib-less, with branches 

 of every order opposite or alternate, very patent and tapering 

 toward the base, mostly obtuse at apices (rarely tapering to 

 slender apices). Tetrasporangia in pinnules forming oblong, 

 spatulate or roundish sori. Cystocarps formed in the middle por- 

 tion of a pinnula, hemispherically swollen on one side. Colour 

 purplish red fading to yellowish. Substance cartilaginous. 



Hab. : On rocks, shells, stones, etc. extending from high tide 

 to tht depth of 4-5 fathoms. Hoko-to (Taiwan) ; Goto Isl.; Provs. 

 Tosa, Kii, Shima, Ise, Idzu, Sagaini, Awa, Kadsusa, Rikuzen, Tsu- 

 shima, Tango, Wakasa and Noto. Ogasawara-Isl. Fruits : spring- 

 summer. 



Fronds attain the height of 10-20 cm. and the breadth of 

 frond vary from 0.5-2 mm. being often very slender in pinnules. 

 The plant takes a very different appearence according to its habit- 

 at. Those growing near high tide are densely pinnate in elegant 

 and regular manner as illustrated in fig. 3, while those in deeper 



