12 M. FOSLIE. [1899 



ought to be specially mentioned. It grows on dense tufts of other 

 algæ. Over a veiy small primary crust is formed a 0.5 — 0.7 mm. 

 thick crust of indefinate shape loosely clinging to the subjacent 

 and the substratum, with more or less irregular surface, the edges 

 free and freqiientl}' bent downwards, and wnth indistinct concentric 

 striæ. It especiallj.' differs from f. conspersa being in the lower 

 part provided \\-ith rather numerous rhizoids which often are cup- 

 shaped and then much resembling those in Lithophyllum expan- 

 sum. This in part free development corresponds with some modi- 

 fication in struciure, though in the main coinciding with that in f. 

 conspersa and especially in parts of that form with new and looseh' 

 connected crusts over each other. The structure is on the whole 

 rather varying in the present species. The conceptacles of sporangia 

 are similar in both forms. 



With reference to relationship may be remarked, that f. spe- 

 ciosa much approaches in habit such forms of LitJiothamniooi 

 2IueUeri which cover the lower part or the root of other algæ, 

 and especially resembling certain forms of L. Engelhartii, but 

 differing as regards the conceptacles, and in structure most nearly 

 agreeing whit that in the present species. However, I ha\"e seen 

 but a solitary specimen. 



Also this species is hitberto onh' known from the Cape of 

 Good Hope. 



Lithothamnion lichenoides (Ell. et Sol.) Fosl. 



Norv. Lith. p. 7; Ell. et Sol. Zooph. p. 131. 



f, pusilla Fosl. mscr. 



Lithophyllum lichenoides Rosan. Melob. pl. 5, fig. I a. b. c. 

 Lithothamnion lichenoides f. epiphytica Fosl. On some Lith. p. 4. 



f. patena (tlook. til. et Harv.) Fosl. 



List of Lith. p. 7; Melobesia patena Hook. fil. et Harv. Ner. austr. p. 111. 



f. depressa Fosl. 



Calc. alg. Fuegia (in press). 



Melobesia lichenoides Harv. Phyc. Brit. pl. 346. 



Lithothamnion lichenoides f. rupincola Fosl. On some Lith. p. 4: ex parte. 



