L30 BYN0P8IS OF BRITISH SEAWEEDS. 



LXWI. MICROCLADIA. 



'^2~k glandulosa (The glandular Microcladid) j frond filiform, 

 compressed, distichously branched, traversed l>\ a wide, ar- 

 ticulated tube, Burrounded by numerous, large, coloured, 

 angular, radiating cells; external coat formed of minute re- 

 ticulated cellules; fructification of two kinds, on distinct 

 individuals: 1, tetraspores immersed in theramuli; 2, 

 silo, roundish receptacles (favella), having a pellucid Km- 

 bus, containing numerous minute angular Bpores, and Bur- 

 rounded by Beveral, short, simple, involucral ramuli, Grev. 

 Alg. Brit.^p. 99. t. 13. (Atlas, PL LI. Fig. 230.) 

 9eria glandulosa, Ag. Fucua glandulosus, Soland. 

 IL'b. Growing on rocks in the Bea, or on Algse, or Sponges, either 

 near extreme low-water mark, or at a greater depth. Yery 

 rare. Annual. 

 As a genus, Microcladia is very closely indeed allied to 

 Ceramium, with which it agrees in habit, and merely dif- 

 fers in some minor points of structure. Some specimens 

 of C. rubrum nearly resemble it, but the absence of ex- 

 iil joints in the Microcladia is a character sufficiently 

 LOU8 to distinguish it from the Ceramium. Microcladia 

 (fhnidulosa is often found tangled with other Alga?, upon 

 ■vhich it grows ; and sometimes creeps over them in the 

 manner of a Cuscuta, throwing out root-like fibres along 

 the branches ; these adhere so strongly that it is impossible 

 lisengage them without laceration. 



LXXXIL CERAMIUM. 



22 . rubrum (The red Ceramium) ; filaments robust, gradually 

 attenuated upwards, irregularly dichotomous, with lateral, 

 forked or multifid ramuli, the apices hooked inwards ; arti- 

 culations coated with coloured cellules, unarmed, the lower- 

 most twice as long as broad, the upper shorter than their 

 breadth ; dissepiments constricted ; tetraspores immersed in 

 the articulations, whorled : tavella? globose, mostly borne on 

 the lateral branchlets, subtended by three or four involucral 

 ramuli, Ag. St/n, p. 60. (Atlas, PL LIIT. Fig. 242.) 



Ceramium virgatum, Both. C. elongatum, Roth. C. axillare, 

 DC. C. nodulosum, Dueluz. C. secundatum, Lyngb. 

 Conferva rubra, Suds. C. nodulosa, Lightf. C. tubulosa, 

 Huds. C. flocculosa, Ellis. 



Hah. Growing on rocks, stones, and the smaller Alg;c, in rock- 

 pools, from near the extreme of high-water to low-water 



