174 



Remarks: Plant in question may be taken at first glance for 

 a species of PolysiphoniLi only differing in the mode of distichous 

 ramification and a single longitudinal arrangement of tetrasporangia ; 

 by these characters, I think, the present plant ought to be placed 

 under the present genus. If my identification proves not to be wrong, 

 the present plant is very remarkable for its having ' Haarblattern "; 

 for no one species of Pterosiplwuia is hithertoknown to have them, 

 as Falkenberg states that in Pterosiphonia " Haarblattern " are 

 entirely wanting. 



PL. XCVIII. Fig. 1 : two fronds of Ptcrosiphonia fibrillosa 

 Okam. n. sp., \. Fig 2-3 : cross-sections of ecorticated portion of 

 branchlets ; 2 : ^fS 3 ^10. Fig. 4 : cross-section of the lower por- 

 tion of a thicker main-branch, ^. Fig. 5 : portion of a pinna, \ e . 

 Fig. 6 : surface-view of a portion of a pinnula, ~. Fig. 7 : growing 

 apex of a branchlet showing the presence of fibrillae (i. e. Haarblat- 

 tern") on flattish surface, 5 p. Fig. 8 : longitudinal section of a branch 

 through the axis showing free-standing of branches, ^*. Fig. 9 : 

 portion of a fibrilla, ^. Fig. 10 : surface view of a pinnula show- 

 'ng the early formation of cortical cells, -*-, Fig. 11 : laciniae of a 

 pinnella bearing tetrasporangia, \*. Fig. 12 : very young antheridia, 

 ^ffi. Fig. 13 : a-tittle advanced antheridium, ^p. Fig. 14 : fully 

 formed antheridium, ^fs. Fig. 15 : young procarp, ~. Fig. 16 : 

 young cystocarp, ^j 5 . Fig. 17 : cystocarps, -~. Fig. 18 : surface- 

 view of a cystocarp showing structure of pericarp, ~.-^Fig. 19 : 

 very young frond just germinated, -. 



Pterosiphonia fibrollosa Okam. $? M- 



V li fc <* 3 iSJ *t W> 



& xcviii ii JK. 

 fig - li ^ ?:' b t> 3t- lili / IS - Wl"f >, iS jfc y, M tfe - IHI 



