35 



371 



C. Urvilliana which are very similar lo C. viipressoides; il is especially the forms 



which she has referred to forma trisdcha (cfr. Weber van Bosse, Monographie, 



pi. XXVI, fig. 8 a and b and fig- 9; especially the last mentioned figure), which remind 



one much of var. flabellata described by me. Finally, certain forms of Caiilerpa 



Freijcineiii, especially the forms Mme. Weber 



VAN Bosse refers to the var. pectinata, show 



a great likeness to C. cupressoides, as she also 



has emphasized herself, and in this connection I 



can quite agree with her statement (I.e. p. 316): 



"II est presque impossible de tracer une limite 



entre ces algues, car plus on cherche, plus on 



trouve de formes intermédiaires qui effacent les 



distinctions qu'on croyait avoir trouvées". So 



long as we do not have experimental cultures 



to rely upon, our limitations of the species and 



forms in such a numerous group as C. cupressoides 



will always be very much a malter of chance. 



In passing now to a more detailed descrip- 

 tion of the forms I have found in Danish West 



India, I may just men- 

 tion that each of these 

 is directly connected 

 with a definite local- 

 ity. Regarding the 

 localities I may here 

 refer to what I have 

 said on this matter 

 in the introduction. 

 I need only mention 

 here, that Caulerpa 



cupressoides is lo be found on more exposed coasts behind 

 the coral reefs creeping here in dazzling white coral 

 sand, that it occurs in sheltered localities in the interior 

 of the lagoon in the often very muddy water we find 

 there, growing in the soft muddy bottom, and finally 

 that it is found in deeper water down to a depth of 

 about 20 — 30 meters; but just as there is a very even 

 and gradual change between these in themselves very 

 different localities, in the same way the forms of C. 

 cupressoides in the different localities are united by 

 transitional forms. But it is just in the above-named 

 localities, where the conditions of life are so very dif- 



48' 



Fig. 13. C. cupressoides (Vahl) Ag. 



var. mamillosa (Mont.) Weber van Bosse. 



From shallow water. Longford (St. Croix). 



(About 1:1.) 



Fig. 14. C. cupiessoUlcs (Vahl) Ag. 



var. typica Weber van Bosse. 



In shallow water. Protestant 



Cay (St. Croix). (About 1 : 1.) 



