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swollen beneath the apices of ramelli, either terminated with a simple, 

 or branched, pointed or expanded apical portion ; often two cysto- 

 carps are formed in a discontinuous longitudinal row in one ramellus. 

 Colour shining purplish red. Substance cartilaginous and the plant 

 does not adhere to paper in drying. 



The alga is perennial and during one year it makes the growth 

 of 1 8-2 1 cm. Of duration of the life of this alga we know nothing. 



Of the anatomical structure, the frond consists of three layers, 

 cortical, infra-cortical and medullary (PI. CXXVII, Fig. 9, a, b, c). 

 The hyaline filaments which are characteristic for the plants of this 

 genus are very dense in the infra-cortical layer and more loose in 

 the medullary. The structure is just same as that of Gelidium 

 ainansii Lam. 



Affinities : The present plant has been taken by early authors 

 for Gelidium cartilagincum Grev. (e.g. Harv. in Gray's List of Jap. 

 Plant no. 13, collected at Shimoda) from the resemblance of the 

 flexuose habit of branches, and of cystocarpic and tetrasporic 

 ramelli. But the mode of ramification is very different in two plants. 

 In Gclidinm cartilagincnin longer and shorter branches do not stand 

 mixed, and the pinnate arrangement of branches is more regular 

 than in ours. Moreover the frond of the former is much larger 

 and more stout, and branches are broader and thicker than the 

 present plant ; also branches (which are more widely patent as al- 

 most horizontal) are a little narrowed at their bases. 



Gelidhim pacificiim, on the other hand, is more robust than 

 G. amansii Lam. with which it is so closely allied that both plants 

 are often confused, and the both grow in the same locality ; but the 

 former prefers the habitat where waves are strong or tidal currents 

 are in a good flow, while the latter is found in rather calm places ; 



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