6 



slightly a few constrictions. This new Canlerpa has characters of 

 different member of this large family." I describe this plant with the 

 following diagnosis. 



C. Okamurai Weber— Frond erect rising from repenting surculus, often geminate, simple 

 or branched, more or less closely inserted with ramenta on all sides ; ramenta in thickness mb- 

 aequal to diameter of cylindrical rachis, obovate or subclavato-cylindrical borne on a short 

 pedicel which arises as a lateral protuberance beneath a few slight constriction of the rachis. 



The plant has a creeping surculus which ramifies in various directions 

 and forms a dense mat. It is cylindrical, glabrous and glossy, and 

 shrinks becoming wrinkled in drying; it is several centimetres long, being 

 1-1.5 mm in diameter. Rootfibres are emitted copiously from surculus 

 at longer or shorter intervals. 



Fronds arise from surculus, often two near together, and are cylin- 

 drical, being simple, or branching irregularly once or twice. They 

 attain a height of 4-12 cm, being as thick as the surculus and are clothed 

 throughout their whole length with more or less densely imbricated 

 ramenta. Ramenta are apparently imbricated in densely clothed fronds, 

 while in loosely inserted ones they appear as if distichus and opposite. 

 The latter disposition of ramenta is more generally the case in those 

 standing near the base of frond, where ramenta are as a rule loosely 

 inserted ; they are gradually imbricated and become closer as they pro- 

 ceed upward. Rachis is slightly constricted at the insertion of ramenta 

 and somewhat bulges out laterally beneath the constriction, giving rise 

 to a short pedicel on which a ramentum is situated. The junction of a 

 ramentum and a pedicel is more distinctly constricted than the constric- 

 tion of the rachis. The form of ramenta varies in several fronds. 

 Basal ones are generally shorter than the upper and they are obovate, 

 while the upper ones are oblong or subclavato-cylindrical, their apical 

 portion being a little thicker than their basal portion. They attain a 

 length of 2-5 mm being ca. 1.5 mm thick, that is subequal to diameter 

 of the rachis. 



Color of plant is brilliant grass-green, which is well preserved in 

 drying, or in older fronds it fades to a dull straw color. Substance is 

 rather firm, and the plant imperfectly adheres to paper in drying. 



The present plant, as Madme. Weber states in her letter, has the 

 appearance of Caulerpa clavifera from which however it widely differs 

 in several points. It shows, on the other hand, some points of resem- 

 blance to G. ambigua mihi in the oblong nature and arrangement of 



