312 EXPLOEATOEY NOTICES FOE JULY. 



vegetate ; and those that do exist degenerate in form 

 as well as in colour. How far below low-water mark 

 the red species extend has not been ascertained, but 

 those from the extreme depths of the sea are of the 

 olive series in its darkest form." 



The olive series most abounds in the tropical seas, 

 the red luxuriates in the temperate zone, while the 

 majority of the vegetation of the Polar seas is green. 

 The lowest forms of the latter, however, (the Ulvce,) 

 are equally distributed through all. Mr. HAEYEY 

 observes, that " Owing to the large size and strictly 

 social habit of our common Fuci and LammaricB, a 

 hasty observer might assume that in the British seas 

 the olive series predominates, and such is undoubtedly 

 the case if we look to individuals and not species. 

 But he will be surprised to find on examination that 

 our submarine meadows are composed, in the main, of 

 not more than ten species of. this race ; while the 300 

 or 400 others, of which the marine Flora consists, are 

 scattered like weeds, and often occur in such small 

 quantities as to escape the notice of any but a botanist. 

 When we speak, therefore, of different types charac- 

 terising different latitudes, we mean merely variety of 

 form, not abundance of production." 



