5 



regular arrangement was here and there disturbed by other ramenta, 

 I came to the conclusion that the first one which I took for a different 

 species is really a form of this species and that ramenta vary somewhat 

 in their dispositions. 



The portion of rachis intercepted between two opposite ramenta is 

 slightly constricted as if articulated ; it is more especially so in frond 

 bearing ramenta constricted at base. In frond bearing ramenta which 

 are not narrowed at base, the constriction of rachis is not so marked. 



By closer investigation of many more collections, the doubtful 

 questions of surculus may be settled, and in that case, this plant might 

 be proved, by the absence of true repenting surculus, to be established 

 as a typical species of a new section ; but in the present state of my 

 knowledge, from the character of ramenta, it seems to me to be more 

 proper to place it under the section Sedoideae, than to establish it in a 

 new section. Among Sedoideae the near ally seems to be sought for 

 Caulerpa sedoides on account of subdistichus disposition of ramenta 

 and spurius articulation of rachis. The form of ramenta, however, is 

 different from C. sedoides, being more oblong or cylindrical, instead of 

 being more spherical. 



Caulerpa Okamurai Weber, n. Sp. 



This new plant is not a species from Ogasawara-jima, but from the 

 Main-island. As it has some resemblance to Caulerpa ambigua mihi I 

 shall describe this plant here by the way. 



The present plant has been collected by several persons, and by 

 myself in several localities of the Main-island (Hondo) such as Suruga, 

 Mikawa, Oki and Noto. It has a rather wide range of distribution. I 

 studied this plant carefully and found it to be allied on the one hand 

 with Caulerpa clavi/era and on the other with G. sedoides; but I 

 hesitated for a long time to determine it as a new species. I therefore 

 sent one of my dried specimens of this species, together with a few 

 others, to Madme. Weber von Bosse and asked her opinion about it. 

 She favored me with the following answer : " The other one is a new 

 species, which I should be glad to call Caulerpa Okamurai, if you will 

 allow me to do so. It has the appearance of C. clavi/era, but if you 

 will examine it through the microscope you will see that the ramenta 

 are borne on small pedicels. The rachis of the little stems also shows 



