b3 



Heterosiphonia pulchra (Okam.) Falkenb. 



Nonii Japi : Shima-dasya. 

 PL. CLXVI, Fig. 1-13. 



Heterosipkonia [>i<lchn< (Okam.) Falkenb. Rhodom. p. 647. Dtisya 

 i-,ni:hni Okam. Contr. to the Know!, of the Mar. Alg. of Jap. II. (Bot. 

 Mag. Tokyo, Vol. X, no. Ill) 1896, p. 34, PI. Ill, fig. 14-16. Helcr.,- 

 sifihniiia iiofo.'/txis Okam. /. c. p. 34, PI. Ill, fig. 17-21. 



Frond epiphytic, 3-6 cm. high, filiform, 200-300 /< thick, not much 

 attenuated above, articulated throughout, 4-siphonous, tereti-compressed, 

 3-4 times pinnate in a full-grown plant, throughly alternate and dis- 

 tichous, with more or less percurrent stem, branching into some main 

 divisions. Basal portion of frond comes in contact with the substratum 

 by means of basal pinnae which are transformed to rook-like fibres. 

 Main branches mostly twice pinnate, very patent, weak and longer 

 below, gradually becoming erecto-patent and shorter above and thus 

 assuming the pyramidal outline. Branches of every order patent, slightly 

 flexuose, elegantly furnished with short pinme of subequal length and 

 take linear outline, but in some, upper branches become decompound 

 and take subcorymbose appearance. Pinnae 1-1.5 mm. long, standing 

 at every 3rd or 4th (or 2nd) node, patent, dichotomous or dichotomo- 

 pinnate, branching and bearing stichidia -ilong the inside of pinnae ; 

 sjme of pinnae often grow up into branches. The number of articula' 

 tions intercepted by branches and pinnae varies from 2-5, rarely more- 

 but 2, 3 or 4 are common in proportion. Pinnulae subulate, mono- 

 siphonous for the most part, some with a few basal cells polysiphonous 



PI. CLXVI-CLXX, March 1920. 



