Ill SYNOPSIS OF BRITISH SEAWEEDS. 



251. floccosum (Pottexferis Cattithem od capillary, 

 very flaccid, remotely much branched ; branches alternate, 



:to-patent, articulated j every joint producing a pair of 

 opposite, simple, Bubulate, erecto-patent, minute ramuli; 

 tetraspores elliptical, pedicellate, produced on the ramuli, 

 near their base, Ag. Sp. Alg. r. 2. p. 158. (Atlas, PI. LV 1 1. 

 Fig. 263.) 



CalUthamnion Plumula, Lyngb. C. Pollexfenii, Harv. Conferva 

 floccosa, Fl. Dan. 



11'iL. North of Scotland. On submarine rocks, near low- water 

 mark. Annual. Spring. Very rare. 

 C. floccosum would appear to be peculiarly a northern 



plant, confined to the coasts of Norway and the north of 



Scotland, iu both which countries it is of extreme rarity. 



252. Turneri (Turner's CalUthamnion)', filaments rising from 

 creeping fibres, simple or repeatedly branched, once or twice 

 pinnated with opposite, spreading, simple ramuli; articula- 

 tions of the main filaments 5-10 times longer than broad; 

 tetraspores clustered, subracemose or corymbose, favella? in- 

 Yolucrated, stalked, Ag. St/st. Alg. v. 2. p. 100. (Atlas, 

 PI. LVIIL Fig. 266.) 



Callithamnion repens, Lyngb. C. variabile, Ag. Ceramium 

 Turneri, Both. C. repens, Ag. Conferva Turneri, Dillw. 

 C, repens, Dilhv. C. tenella, Dilhv. 

 Hab. Parasitical on other Algae, between tide-marks. Annual. 

 Summer. Not uncommon. 

 This pretty little species of Callithamnion, named by 

 Dr. Roth after its discoverer, Mr. Dawson Turner, was first 

 observed on the Norfolk coast, and has since been found 

 on most of the shores of Europe, where it not uncommonly 

 creeps over the fronds of various small Alga?. The fructi- 

 fication differs in some respects from that of other Calli- 

 thamnia, and shows an approach to Griffiths! a, especially in 

 the involucrated favellae. The tetraspores are however not 

 so regularly disposed as in that genus ; and the habit is 

 more like that of CalUthamnion. 



253. barbatum (The bearded Callithamnion): stems (rising 

 from creeping filaments ?) much and irregularly branched ; 

 branches mostly alternate, long, Bubsimple, naked, or pin- 

 nulated with minute, opposite, spine-like, erecto-patent ra- 

 muli ; articulations twice or thrice as long as broad , tetra- 

 spores elliptic-oblong, with a wide limbus, b< ssile on the sides 

 of the pinnules, Ag. Sgst. Alg. v. 2. p. 181. (Atlas, PL 

 LTI. Fig. 256.) 



