47 



%^ 



Taking now all the particulars mentioned above as charac- 

 teristic of Clad, membranacea, referring also to the other species 

 belonging so far as we 

 know to the genus it is 

 clear, that Cladophoropsis 

 shows great differences 

 from the Cladophoracese 

 while it can be placed 

 on the other hand in a 

 natural way in the family 

 of the Valoniaceas, being 

 very nearly related to the 

 genus Boodlea. From 

 Cladophoropsis Boodlea 

 nevertheless is easily re- 

 cognizable by the pre- 

 sence of cross walls at the base of the branches, in any case in 

 the older part of the thallus, and of apical tenacula in the end 

 of the branches. 



Fig. 32. Cladophoropsis membmnacea (Ag.) Borgs. 



a, chromatophores and nuclei, h, cristals, 



c, chromatophores with pyrenoids. (a and c, 



250:1; h, 100:1). 



1. Cladophoropsis membranacea (Ag.) Borgs, 



BoRGESEN, F., 1. c, 1905, p. 275. Vickers, Phycologia Barbadensis, 

 p. 20, pi. XVII. 



Siphonocladus inemhvanaceus (Ag.) Bornet in Journal de Botanique, 

 vol. 1, 1887, p. 56. 



Conferva membranacea Ag., Systema, p. 120. 



Cladoph. membranacea is a common species at the shores 

 of the islands, where it occurs both in sheltered and in more ex- 

 posed places. In the last mentioned localities it is found growing 

 on rocks covering them as a low very dense cushion constantly 

 dashed by the waves. Furthermore, it occurs epiphytic upon 

 other algae especially Gelidiimi rigidum and finally it is found 

 as /Egagropila-\\ke clumps lying loose upon the bottom and cast 

 ashore often in great quantities. 



As I have mentioned above and also in my earlier paper, 

 the cushions or clumps consist of numerous filaments woven 



rigidus of Howe (Phycological studies, I, in Bull. Torr. Bot. Club, vol. 32, 

 1905, p. 244) published at nearly the same time as my paper on Sipho- 

 nocladus, cannot after my opinion in a natural way be grouped in the 

 genus Siphonocladus as confmed by me. On the other hand, it 

 seems to me that it can without difficulty be considered as a Clado- 

 phoropsis, being especially related to CI. brachyartra, as is also pointed 

 out by Dr. Howe (1. c). 



