48 SYNOPSIS OF BRITISH SEAWEEDS. 



narrow spores distinguish it. It comes nearer to M. 

 gulans, bul differs in the position of the Bpores. The 

 only specimens which 1 have seen were collected by Mrs. 

 Griffiths several years ago. They were found on Cera- 

 rubrum, which they covered nearly as closely as the 

 warts of fructification cover Stilophora rhizodes. Pro- 

 bably it may be found on many of our coasts. 



G9. clavatum (The dulled Myrionema) ; "very minute, rather 

 convex; filaments clavate, mostly bifid; spores obovate, 

 pedicellate, affixed to the filaments," Harv. in Hook. Br. Ft. 

 v. 2. p. 391. (Atlas, PI. XVIII. Fig. 75.) 



Linckia clavata, Carm. 



II ah. On a thin pui-ple cartilaginous crust, probably a Verru- 

 caria, which covers the pebbles at the half-tide level 

 Autumn. 

 Of this curious little parasite I know nothing more than 



is learned from the above short description, which, with 



the figure, is copied from Capt. Carmichael's manuscripts. 



Oedee 6. ECTOCARPACEM. 

 XXXII. CLADOSTEPHUS. 



70. verticillatus (The tohorled Cladostephus); branches slender; 



ramuli mostly forked, regularly whorled, the whorls at short 



intervals, Ag. Syn. Int. p. xxv. (Atlas, PI. XIV. Fig. 58.) 

 Cladostephus myriophyllum, Ag. Ceramium verticillatum, DC. 



Conferva verticillata, Lightf. C. myriophyllum, Roth. C. 



ceratophyllum, Roth. Fucus verticillatus, Wulf. 

 Hah. On rocks, stones, and corallines, within the influence of the 



tide. Perennial, fruiting in winter. 

 A well-known species, abundant on most of the shores of 

 Europe, and found, according to Vlartius, in Brazil. It was 

 originally described by Lightfoot, whose excellent specific 

 name I retain in preference to that of Eoth, conferred nearly 

 thirty years subsequently, and which is universally adopted 

 on the Continent. What I consider fruiting ramuli are 

 regarded by Italian authors, the accurate and acute Mene- 

 ghini included, as a parasitical plant. 



71. spongiosus (The spongy Cladostephus); branches thick and 



clumsy ; ramuli mostly simple, sometimes forked, irregularly 

 whorled and densely imbricated, Ag. Syst. p. 168. (Atlas, 

 PL XVII. Fig. 71.) 

 Cladostephus laxus, FL Dan. Conferva spongiosa, Huds. Fucus 

 hirsutus, Linn. 



