46 BRITISH SEA-WEEDS. 



of Sea-thongs would be best translated by the latter 

 word, and that probably is correct. This genus con- 

 tains but one species. 



Hunanthalia lorea. Leather-thong Himanthalia, 

 or Sea-thongs. 



This is conimoa on the Atlantic shores of Europe, 

 and has been found on the coast of North America. Its 

 chief peculiarity consists in the very large proportion 

 that the spore-receptacles bear to the whole plant. 

 These are commonly three or four feet long, and are 

 said to attain a length of even twenty feet, while the 

 little button frond is never more than an inch or an 

 inch and a half high, and about two inches in diame- 

 ter. Great diversity of opinion has been expressed as 

 to the duration of this plant, — some writers asserting 

 it to be annual, some biennial, and some even peren- 

 nial. My own recent observations of a very large num- 

 ber of growing specimens in early spring lead me to the 

 conclusion that the middle course is, as usual, the cor- 

 rect one, and that it is biennial. It certainly is not 

 annual ; but I am not prepared to say that it may not 

 be perennial. 



Order II. SPOROCHNACE^. 



Fronds without joints. Spores attached to external, jointed 

 Jilaments, either free or compacted together. 



Genus VII. DESMARESTIA. 



Frond linear, either thread-like or more or less flat, 

 branched, with a single-tubed, jointed thread running 

 through it, when young bearing marginal tufts of branch- 

 ing fibres. Fructification unknown. 



