Odonthalia ochotensis (Rupr.) J. Ag. 



Norn- Jap. : Shinobuba-nokogirihiba, 



PL. CXCVI, Fig. 1-6. 



Odonthalia ochotensis (Rupr.) J. Ag. Sp. Alg. II, p. 897 ; DC 

 Toni Syll. Aig. IV, p. 1140. Atomaria oc/iotcnsis Rupr. Alg. Ochot. 

 p. 20 (212), tab. 9. 



Fronds coespitose, rising from a common scutate disc (?), 

 flat, linear, alternately decompound-pinnate, distichous, thickened 

 below into sub-cylindrical stem, soon complanated above ; in the 

 lower portion of frond margins are rough by remains of dropped 

 branches. In older frond the lower portion is transformed into a 

 thick cylindrical stem, and the plant attains the height of 20-30 

 cm. Rachis scarcely exceeding i mm. in breadth, evidently pro- 

 vided with midrib and marginated, gradually becoming a little 

 broader and more membranaceous upward, 1.5-2 mm. in breadth. 

 Midrib becomes prominent by evolution of cortical layers almost 

 occupying the median portion of branch and very gently flexouse. 

 Pinnae arise from margin, and similarly shaped pinnae also proli- 

 ferated from margins are attenuated at the base in young 

 stage, but when fully grown become almost equally broad. 

 Sterile ones are elongated, while fertile ones more contracted, 

 more flabellate and all stand erecto-patent. Pinnulae dentiform or 

 elongated, in some almost subulate, slightly incurved in upper 

 ones. Stichidia formed in terminal or lateral pinnae, flabellato- 

 corymbose, pinnato-fasciculated, each provided or not provided with 

 a short pedicel, linear-lanceolate, slightly contracted at every arti- 

 culation, containing double row of tetraspores that is with two 

 oppositely placed tetraspores in a single articulation. Cystocarps 

 obliquely situated beneath the apex of pinnule and calcalated, 

 PL. CXCVI CC, March, 1923 



