54 



form a connected whole. Sometimes, but more seldom, I have 

 found two tenacula growing out from the same top of the cell. 



In the frond the lowest cell in the midrib is considerably 

 larger (about 3 times) than the other cells in it, as is the case also 

 in Striwea anastomosans. 



With regard to the cell-wall this is rather thick in the lowest 

 part of the stalk, growing thinner upwards and in the frond. The 

 wall shows longitudinal and transverse striations, as is also men- 

 tioned by Murray and Boodle (1. c. p. 271) for Striwea pliimosa. 



As to the wall plasma and its contents this is very like what 

 we find in Valotiia. The chromatophores (Fig. 38^) are plate- 

 shaped, of irregular polygonal form, often with elongated angles 

 forming in this way a net-work. In each chromatophore a rather 

 large pyrenoid is nearly always present. Behind the chromato- 

 phores we find the numerous nuclei rather regularly distributed. 



The whole plant with stem and frond together reaches a 

 height of about 10 cm, the length of the frond may measure up to 

 4 cm and the breadth 2 14 cn^- The stalk is normally unbranched 

 but a single specimen was found having a side-branch also crow- 

 ned with a frond. 



This species seems to be rather nearly related to Striivea ana- 

 stomosans by its large basal cell in the frond and by the mode 

 of ramification, but this is much more regularly distichous, the 

 frond has another form, is longer, containing several, more oppo- 

 site pairs of branches, the top cells in the branches of the first 

 order are longer etc. ; furthermore, the stem has a number of 

 annular constrictions at its base, which is not the case in Striwea 

 anastomosans and finally, the size of our plant is much larger. 



Striwea elegans was dredged in deep water only, down to 

 about 40 meters. 



It occurs at several places in the Sound bet\veen;~^St. Thomas and 

 St. Jan, further near Thatch Cay at St. Thomas where it was collected 

 by Dr. Th. Mortensen and off America Hill on the north side of St. Jan. 



2. Struvea anastomosans (Harv.) Piccone. 

 A. Piccone, Alghe in »Crociera del Corsaro alle Isole Madera e Cana- 

 rie del Capitano Enrico d'Albertis«, p. 20, Genova 1884i). Cladophora? 

 anastomosans Harv. in Trans. R. I. Acad., vol.22, p. 565; Phycologia Au- 

 stralica, vol. II, pi. 101. Borgesex, I. c, p. 268. 



^) The variety canariensis of Piccone described here is = Struvea ramosa 

 Dickie, as pointed out by Mirray and Boodle. 



