260 SEAWEEDS 



plants, thus juxtaposed, each independent of the 

 others, though inclosed within a common envelope, 

 and not trichome-formations as in the Nostocacccc. 

 The filaments so formed by the colony ramify within 

 shells often in company with Gomontia and Mastigo- 



lla cccspitosa. a, young tnallus, one ot tne brandies divided 

 into numerous cells ; b, sporangia highly magnified. (After Boriiet and 

 Flahault.) 



colcus, and effect the disintegration of the shell sub- 

 stance. Propagation is effected by the liberation of 

 vegetative cells from the envelope (not in hormogo- 

 nia), and by spores formed in sporangia by successive 

 divisions of the protoplasm. Dermocarpa occurs as 

 an epiphyte on other Alga?, and consists of clusters 



