23 C R . YPTOGAMIA ALG^E. 



2. P.fucoides, blackish-brown ; stalk rigid below and bare, much 

 branched ; branches irregularly alternate, the ultimate ones pa- 

 tent, crowded and dichotomous at the top ; articulations longer 

 than broad or equal; tubercles ovate, subsessile. GREV. Ft. 

 Kdm. 308. Conferva fiwmdrs, DILLW. Conf. p. 81. t. 75. fig. 1. 

 and 3. Hutchinsia fucoides, HOOK. Scot. ii. 87. Hut. ni<jrescens* 

 LYNG. Ilydroph. Dan. 109. t. 33. 



Hab. On rocks and other Algae, very common. 



From 4 to 6 inches long. The stalk is as thick as stout 

 thread, rigid, black, rough below with the remains of for- 

 mer branches, soon giving off several long compound 

 branches, arid becoming very bushy upwards. The supe- 

 rior branches are dull reddish-brown, and rather flaccid, 

 fasciculate, dichotomous, tapered, generally marked with 

 imbedded tubercles, and terminated with many pellucid 

 fibres- The articulations of the stem are shorter than 

 their diameter ; in the branches they are equal or about 

 one-half longer ; all are distinctly polystriate. Adheres . 

 imperfectly to paper. Subject to some variety, and yet 

 the practical botanist recognises it without difficulty by 

 its dark dull colour, its rigi(\ stalk, elongate flattened form, 

 and the bushiness of the superior branches. The descrip- 

 tion which LYNT.UYI: has given offftttchinsia vio/mra is by 

 no means applicable to our plant, which appears to be his 

 //. nigrescens. 



3. P. nigrescens, reddish -brown ; stalk filiform, continued 

 throughout, very much branched ; branches irregular, compound, 

 spreading, fibrilose ; articulations about one-half longer than their 

 breadth. GREV. in I'M. flutchinsia niy rearms, AGARDII. Conferva 

 itiyrcscens, DILLW. Sy-n. p. 81. 



Hob. Coast near Berwick, rare. 



Our specimen of this species has been compared by Dr GIIK- 

 VILLE with a specimen of //. nij/rrwnx from ACIARDH, with 

 which it agrees, so that no doubt can be entertained of the 

 synonym. It is nearly allied to the preceding, and h;is 

 often perhaps been confounded with it, for I think it pro- 

 bable that the middle figure (2.) of DILLW YN'S, tab. 7^-, 

 represents this plant rather than any variety of P. fttcoides. 

 Several stems aris^ from the same base, the whole forming 

 a tuft 3 or 4 inches in height. Each stem is continued 

 throughout of the thickness of sewing thread, branched on 



