122 



lagoons, where as I have already mentioned in my earlier papers^) 

 it is one of the most common algee in the very characteristic algal 

 vegetation, which covers the mangrove roots. As a dark-green, 

 6 — 7 cm. high covering it grows quite dense on the roots and like 

 most of the other richly ramified mangrove algae gradually collects 

 mud and organic particles between its fine ramifications. 



By reason of the exceedingly dense mode of growi^h, arising 

 from the fact that the creeping rhizomes on the mangrove roots 

 are woven together and form often a thick layer composed of the 



Fig. 95. Caulerpa verticillata J. Ag. 

 From the Lagoon of Christianssted, St. Croix. (IM'j:!). 



intertwdned rhizomes, mud etc., and from the fact that the older 

 rhizomes die away by degrees, there will gradually arise a great 

 many separate plants the bases of which often consist of fragments 



to be found in the Botanical Museum of the University of Copenhagen, 

 has however the ramuh rather distinctly arranged in whorls. Harvey's 

 paper, List of Friendly Islands Algae, I have not been able to see. 

 ') F. BoRGESEN og OvE Paulsen, Om Vegetationen paa de dansk-vest- 

 indiske 0er Kobenhavn 1898 (Bot. Tids. 22). (French edition in 

 »Revue generale de Botanique, vol. 12, 1900). 



F. BoRGESEN, A contribution to the knowledge of the marine Alga 

 vegetation on the coasts of the Danish West Indian Islands (Bot. Tids- 

 skr. vol. 23, 1900, p. 49). The algal vegetation of the lagoons in the 

 Danish West Indies (Biologiske Arbejder tilegnede Eug. Warming, 

 p. 41, 1911). 



