THE MARINE BOTANIST. 151 



M, agariciformis. Lying* on the sandy bottom 

 of quiet bays, in two to three fathoms water. 

 Roundstone Bay, Cunnemara. Globular, hollow, 

 foliations delicate. ^^The colour when recent is 

 more or less ting-ed with a rosy pink ] when dry it 

 fades to a yellowish white, and when exposed to the 

 sun becomes perfectly white and rapidly crumbles 

 to powder." 



M. lichenoides. On rocks in tide-pools, near low 

 water-mark. Not uncommon. Perennial. Detached 

 at the margins of the lobes, spreading over rocks, 

 and resembling the leafy lichens. Some varieties 

 of this plant are at times so much like small exam- 

 ples of the former species, that, according to Dr. 

 Harvey, the difference in habit may be caused 

 by the different depths at which these plants 

 vegetate. 



3L memiranacea. Common on the leaves of 

 Zoster a J the fronds of Cliondrus crispus, &g. An- 

 nual. Summer. Minute, dot-like, very thin, and 

 almost membranaceous. Ceramidia, one or two, 

 depressed. Pale purple. 



