40 BY2TOP8I8 OF BRITISH SEAWEEDS. 



G-igartina flagellifoimiB, Lamour. Fucus Qagelliformis, Fl. Dam. 

 Hub. Atlantic shores of Britain. On rocks and stones in the sea, 



between tide-marks. Annual. Summer. Common on the 



shores of the British Inlands. 

 A vi TV commoD planl in the North Atlantic, bu1 Btrangely 

 misunderstood by early writers, who confounded it with 

 Qracilaria confervoides, a mistake which, with modern 

 microscopes, it would he impossible to fall into. The fruc- 

 tification, which was first described by Turner, has been 

 overlooked by many authors, and yet it is not unfrequently 

 produced. I have generally found an abundance of spores 

 in full-grown plants gathered in the months of July and 

 August. They may most easily be elicited by compress- 

 ing a small part of a branch between two pieces of glass, 

 and appear to exist in equal numbers in all parts of the 

 plant. 



52. divaricata {The divaricate Chordaria); frond irregularly 

 divided ; branches divaricate, subdichotomous, flexuous, fur- 

 nished towards the apices with short, very patent, mostly 

 forked ramuli ; filaments of the periphery capitate, Ag. Syn. 

 p. 12. (Atlas, PI. XII. Fig. 48.) 



igloia divaricata, I\1z. 

 Hab. Belfast Lough. Annual. Autumn. Thrown up from deep 

 water, at Carrickfergus. 

 The branching of this species is sufficiently unlike that 

 of C/wrdariaflagelliformis, resembling much more closely 

 that of Stilojyhora rhizodes, to which outwardly our plant 

 bears a very great resemblance. But besides a difference 

 in habit, it is well distinguished from C. Jiagelliformis by 

 the shape of the filaments of the periphery, which in that 

 species are club-shaped, while in this they are slender, but 

 terminated by a large globular cellule. In this respect 

 there is a resemblance to a Mesogloia, but the structure of 

 the axis is exactly that of Chordaria. 



XXYII. MESOGLOIA. 



53. vermicularis (The worm-like Mesogloia); frond unequally 



di -tended, clumsy ; branches irregularly pinnate, thick, worm- 

 like, lineari-fusiform ; ramuli copious, Jong, flexuous, resem- 

 bling the main branches, Ag. Sgn. p. 126. (Atlas, PL XIV. 

 Fig. 55.) 

 Trichocladia vermicularis, Harv. Helminthocladia vermicularis, 

 Hart). Eivularia vermiculata, E. Bot. Chactophora vcrini- 

 culata, Hook. 



