THK CEYLON SPECIES OP CAULERPA. 



I;{1 



should be classed as independent, as a special elementary species, and that the others should consequently 

 be subordinated to it as varying in different directions. 



Also such a form as C. imbricata might be directly attached to C. Chemnitzia, i.e., by means of the 

 little /. mixta with the cylindrical basal pinnules. But since this lacks the slowly tapering trumpet-shapefl 

 branchlets, this is a reason that opposes such a suggestion. 



Oeografhical distribution. — Ceylon : only the North parts : Jaffna! Kangesanturai (from somewhat 

 deeper water) ! South India : Paumben Pass ! Red Sea ; Indian Ocean ; Atlantic (West Indies) ? 



15.— CAULERPA PELT ATA, Lamouroux. 



J. G. Agardh, Till. Algernes Systematik, I., p. 37. 



Syn. C. peltata v. typica (pro parte) Weber v. Bosse, Monographic dee Caulerpes, p. 375. 

 This species has a characteristic mode of branching and growth (fig. 31). From the rather coarse 

 horizontal axes spring long vertical axes with plenty of peltate branchlets. As the illustrations of this 



Fig. 31.— C. peltata (lam.). (1 X 1). 



plant which occur in literature are rather unsatisfactory, I have in fig. 31 given a 

 picture of the typical peltata form. The disc-shaped branchlets are more or less 

 closely set, but in every case they radiate in all directions with the peltate assimila- 

 tion discs directed obliquely upwards. It is precisely this direction of theirs which 

 does not appear in the figures of this form which occur in literature, and which have 

 probably been drawn from dried material. So in Weber, v. Bossb's monograph, 

 where otherwise so many Caulerpas have been excellently reproduced, the figure of C. 

 peltata {loc. cit. PI. XXXI. 9) is scarcely happy, and in Reinke's work on Caulerpa 

 only a dwarf-form with discs pointing in one direction is drawn. The length 

 of the vertical axis naturally varies very much from 1 up to 10 cm. The diameter 

 of the discs also varies, but the average diameter may be said to be about 3 mm. 

 This form does not, as a rule, occur in the uppermost part of the littoral region, but 

 somewhat lower down. It is consequently never exposed at low water, but can then 

 be seen with its long axes swaying to and fro in the swell. This was the case at 

 Kosgoda, where it grew on stones in densely shaded pools together with such a 

 typical deep form as Didyurus purpurascens. In very similar cucumstances it 

 grew also at Kangesanturai on the island of Jaffna. At the last-named place I 

 observed a rather remarkable form ; fig. 32 is a picture of it. It is a largely 

 branched, elongated form of which the majority of the branchlets are typical peltata 

 branchlets Some of the assimilators, however, are clothed only at the base and a little way up with 

 such branchlets : at the top, on the other hand, branchlets of a different kind are developed, especially on 

 the side axes : the joints become longer between the different branchlets, at the same time as their discs 



Fig. 32.— C fidtata 



(lam.) f. ad nwiwmu- 



laiiam. (3 x 1). 



