302 BRITISH SEA-WEEDS. \Ii1iodosjperme(B. 



away, and tlie rigid divaricating branches remain in their 

 nakedness. It seems to be one of those that come by fits 

 and starts. In the early part of the summer of 1847, for 

 nearly a month, it was frequent on the shore at Ardrossan 

 and Saltcoats at almost every tide ; whereas in the summer 

 of 1848 very few specimens were seen. In the summer of 

 1850 some plants were obtained, but not in beauty. Pro- 

 fessor Harvey says, in Phyc. Brit., PI. cxlvi., that though 

 it resembles Poli/siphonia elongata in miniature, it may be 

 readily known from it by the pellucid articulations visible 

 in all parts of the plant, and by the ramuli not tapering to 

 the base ; and in his Manual he tells us that it may easily 

 be distinguished by the distinctly-jointed branches, and by 

 the parallel (not reticulated) veins which they contain. 



24. PoLYSiPHONiA BYssoiDES, GrevilU. 



Hab. On rocks, &c., in the sea. Annual ? Summer and 

 autumn. It is said to be abundant on the eastern and 

 southern shores of England and Ireland ; but rare in Scot- 

 land and in the west of Ireland. We can state that during 

 some seasons it is very frequent on the coast of Ayrshire. 



The time of the year when it is most abundantly got is 

 in the month of August, when it is driven out by the tide 

 in large tangled masses, often intermingled with the beau- 



