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HISTORICAL REVIEW OF THE FLORIDE^.— I. 

 By a. H. Church, D.Sc. 



To the algologists of the last century, as soon as the vegetation 

 of the tide-range began to be familiar, and Red Algaj were differen- 

 tiated from the larger Fuci, the Floridese proved at once an attractive 

 and wholly mysterious race of organism, tlie types of which in their 

 kaleidoscopic variety of form, the transient charm of their rosy 

 coloration, so different from the predominant green of land- vegeta- 

 tion, and their delicate texture and ramitieation, have been very 

 generally accepted as representing tlie culminating race of marine 

 algse. Yet many are stout strong f)lants, attaining to a bushy mass 

 3-6 ft. in length, and the residual tj^pes of the tide-range may 

 present no special attraction either in colour or form, though valued 

 from an economic standpoint and utilised as food by man and cattle. 



The observations of Bornet and Thuret on the nature of their 

 reproductive processes, so distinct from the general flagellated 

 mechanism of other algal phjda, added to the wonder of the group ; 

 and the more the t3^pes have been investigated the more mysterious 

 have appeared their special attributes : only within the last few years 

 has the general scheme of the Life-cycle been rendered clear, and its 

 relation to that of other algal phyla made intelligible. All these 

 features appear the more remarkable as this strange algal race, 

 living in the sea — by no means relegated to deep water as is 

 popularly supposed, but side by side with other residual phyla of 

 ' green ' and ' brown ' algse, — still holds its own in more quiet en- 

 vironment as a race of marine phyt^benthon which has passed to the 

 limit of marine possibility in its reproductive processes. In so doing 

 it throws a curious light on the historj^ of the early sea, as also on the 

 possibility of the landward migration of comparable algal forms to 

 constitute the flora of the land — whether as higher types of auto- 

 trophic vegetation, or as reduced and heterotrophic fungi. 



In the collection and elucidation of the multitudinous forms so far 

 included in this isolated group, the jDioneer algologists of this country 

 have done perhaps more than those of any other in establishing the 

 foundations of the subject ; though in more recent years the more 

 critical work has been done elsewhere, as laboratory technique replaces 

 shore-collection and the cult of the sea-weed album. Once it is 

 understood that the best plants in optimum growth can be only 

 obtained by dredging in the sub-littoral zone, and that the highest 

 laborator}^ technique is required to bring out the most essential 

 details, the plants are largely relegated to the cytological expert. 

 But much remains to be done in other directions of structure and 

 anatomy, the physiology of metabolism, oecological relations, and 

 above all in culture, which is within the scope of the most elementary 

 laboratory practice ; and a wide field still remains open to the algolo- 

 gists of this country, as also to those of British colonies with even 

 hner subtropical reptresentatives of the group. 



The history of the Florideae in its earlier phases is bound up with 

 JouRKAL or Botany. — Vol. 57. [November, 1919.] y 



