368 



Dansk Botanisk Arkiv, Bd. 3. Nr. 1. 



The mother-cell of the tetrasporangium increases much in size, 

 especially in length, it becomes densely filled with granular contents 

 and divided zonately in four spores. 



The cystOcarps are figured by Harvey, 1. c. They form rather 

 large semiglobular bodies upon the branchlets with an opening in 

 the upper end. 



This plant has been found as well in shallow as in deep sea 

 down to a depth of about 30 meters. When growing in shallow water 

 the plant is very robust and does not reach any great height; in deep 

 water it becomes more slender and more than a foot high. When 

 found in shallow water it occurred in more protected places. 



It was found with tetraspores and cystocarps in the month of 

 March. 



St. Croix: In the harbour of Christianssted. St. Thomas: Near the 

 East end of the island; near Thatch Cay (leg. Dr. Th. Mortensen). St. 

 Jan: Cruz Bay, near Great St. James. 



Geogr. Distrib.: Florida, West Indies. 



Genus incertæ sedis. 



Wurdemannia Harv. 



1. Wurdemannia setacea Harv. 



Harvey, W. H., Nereis Bor. -Am. 



Fig. 360. Wurdemannia setacea Harv, 



Part of the thallus. 



(About 7i). 



Part II, p. 246. Kitzing, F., Tab. 

 Phycol., vol. XIX, tab. 26. 



The plant forms low, 

 dense tufts or cushions upon 

 other algæ, stones etc. It 

 consists of a filiform, terete, 

 rather rigid thallus, ramified 

 very irregularly to all sides 

 and felted together (Fig. 360). 

 Some of the branches grow 

 out to main branches, others 

 remain shorter or longer get- 

 ting a spinelike appearance 

 with their acute summits. 

 The thallus is fixed to the 

 substratum by means of 

 small discs which can be 



