SPOROCHNACE^I. 4£ 



This genus is named in honour of the . celebrated 

 French naturalist/ A. 1 G. Desmarest. It does not con-, 

 tain many species, but is J nevertheless widely ^ distri-. 

 buted, and ranges overall the temperate and cold regions 

 to the utmost limits of marine vegetation. The young 

 and mature states of most of the' species are very, differ- 

 ent, and puzzle those" who see them for the first time. 

 All the species not 1 only decay very quickly after being, 

 gathered, but also " cause 1 any other weeds with j which, 

 they may come in contact to do the same. They should,, 

 therefore, always be kept separate, and laid .down as. 

 quickly as possible.'" . • u -_.. _ ,, 



Desmarestia ligulata, Lignlate Desmarestia. 



Frond flat, with an indistinct midrib, repeatedly pinnate ; 

 branches and branchlets opposite, tapering towards both 

 ends. -j, J ^ 



Ccommon all round our coast. It varies chiefly in 

 the width of the branches, whicli in some specimens is 

 nearly one-third of an'inch, while in others it is scarcely 

 greater than in the filiform fronds of D. viridis, for which 

 it is in consequence sometimes mistaken. - 



Desmarestia pinnatmervia. » Pinnately-nerved 

 Desmarestia. 



Frond flat, leaf -like, with waved edges, frjOn^ fojj,rinche^ : 

 to a foot or more long, and from an inch to two or even 

 three inches broad, of a pale olive colour,, and membranous, 

 texture, traversed throughout- by- a distinct mid- vein, from, 

 which spring exactly opposite side-veins.' *■'" 



This interesting plarrt'is a comparatively recent addi- 

 tion to the British marine ftdrai' ana its Jitfe to bp con-, 

 sidered a distinct species is still in doubt. , The.firsl 



