4 



Caulerpa ambigua Okam. mscr. 



A few fronds of this plant were found entangled amoDg other 

 algaa and sponges. I found this plant to be a new species with the 

 following diagnosis :— 



C. ambiqua — Frond dwarf, filiform, isolated with no repenting sureu]u=, erect, rooting 

 downward, divaricately branching above, loosely inserted with ramenta on all sides; ramenia, 

 subaequal to or surpassing the diameter of the rachis in breadth, cylindraceo-clavate, obtuse at 

 apex, equally broad or a little constricted at base. 



If my observation is not at fault, the present plant is very peculiar 

 for the absence of repenting surculus, a well known and well distinguished 

 character common to all the species of this genus known up to this day. 

 All the examples were obtained isolated, none being united to a com- 

 mon repenting surculus. The lower portion of a filiform frond elongates 

 below to form a descending axis, which is unequal in the breadth along its 

 whole length, being here and there swollen at longer or shorter intervals, 

 and root fibres, branching again and again, are mostly emitted from 

 the swollen portions. I have searched vainly for repenting surculus in 

 all the examples, and have not find one except the lower elongated 

 portion of frond, which should be taken as a surculus, not repenting 

 but erect. 



Frond is filiform, dwarf, attaining a height of 1-2 cm being ca. 

 100 fi thick, slightly tapering upward. It branches divaricato-alternately 

 and branches are loosely closed with ramenta. Ramenta are typically 

 distichus and opposite ; but this regular disposition is disturbed by the 

 presence of some irregularly inserted ones. They are separated by 

 wider distances and the rachis is distinctly visible through the interstices 

 They are oblong or obovate, being slightly swollen upwards, and are 

 neither falcate nor pointed, but very patent, straight and very obtuse 

 at apex. The Ibises of ramenta are sometimes equally broad or a little 

 narrowed as if pedicellated. Eamenta attain in a fully grown frond a 

 length of 216-354 ju ; the shorter one half that amount, The breadth is 

 almost equal to or a little thicker than the diameter of the rachis in 

 swollen ones, being somewhat slender in the more cylindrical ones. 

 In a very small specimen attaining the height of 3 mm, I found ramenta 

 very patent, distichus and straight, equally broad at both ends. At first 

 I took it for another species ; but when, afterward, in larger ones which 

 have ramanta in a similar form and arrangement, I found that this 



