THE CEYLON SPECIES OF CAULRRPA. 



121 



manner of growth that this Gaulerpa in a natural state assumes a very characteristic appearance, which 

 can be gathered from Mrs. Pease's description of the mode of growth of this plant in Jamaica when 

 she says : (F. S. Collins, " The Algre of Jamaica," p. 237) : " Gaulerpa davifera grew Uke little clusters 

 of green grapes in big raggy masses." Turner has also succeeded in describing the same characteristic 

 appearance in his " Historia Fucorum " I., p. 126 : " The name of F. davifer has been taken from thie 

 appearance of the plant when recent, in which state the branches look as if merely a cluster of small clavate 

 bodies." But the idea of this mode of growth cannot be clearly gathered from even carefully prepared 

 herbarium specimens (cf. for instance Wittr. et Nordst. Alg. Exsicc. No. 345 as 1,204), and this fact 

 has not been sufficiently pointed out in the descriptions. 



This C. davifer a is a pronounced littoral alga, which is only met with exceptionally in 

 deeper water, and then often under a changed appearance. I have frequently seen it so 

 near high- water mark that at low- water it is only washed by the swell and is thus always fully exposed 

 to almost the whole strength of the tropical sun. And, pressed against the substratum as it is, it 

 might not unappropriately be compared with that type of heath-plants which has been called " espalier 

 plants " (Warming)— it then receives that strength of Ught from practically one direction only. 



With respect to the size of the spherical branchlets, this varies a little. In general the majority 

 of the forms seem as if thfey ought to be referred to the /. macrophysa, at least acoording to Weber v. 

 Bosse's definition of this form in her Monograph (p. 361). 



Fig. 14. — C. davifera (turn.) c. ag. f. remota n. /. (1 x 1). 



As has been mentioned above, C. davifera forms are, as a rule, never met with in other places 

 than in the uppermost part of the littoral region. Sometimes, however, one can find in deeper water 

 a Gaulerpa form whicla apparently is closely related to davifera. Fig. 14 shows such a one, which I found 

 at Galle in a dark deep pool growing on another alga. It differs in that the vertical axis system has been 

 elongated and the branchlets or pinnules have been separated, and especially in that the stalks of the 

 branchlets are often considerably longer than the spherical vesicles, wliile the main axis itself has been also 

 considerably elongated. The whole plant gets through this, a habit wliich reminds one of G. Lamourouxii, 

 at least its forms which have always cylindrical main axis. The original /. Lamourouxii, as it was described 

 by Turner — and according to him by C. A. and J. G. Agardh — had only cylindrical axis. But, owing to 

 the occurrence of transition forms to such forms as have flat axis, Weber v. BossE has brought together 

 all these forms under var. jLawoMrottm,\vhich thereby has received a very extended sense. 

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