HISTORY 13 



described new species and also studied reproduction in Conferva^ 

 Bryopsis, Fucus and Griffithsia. 



In 1854-5 the great French algologist Thuret produced his 

 wonderful monograph on fertilization in Fucus. He also puzzled 

 over the problem of Cutleria, a plant in which apparently there 

 were only sexual organs of reproduction. Although he reaUzed that 

 the Ufe history of this plant offered a problem it did not fall to his 

 lot to find the solution. About the middle of the nineteenth century 

 W. H. Harvey in England produced a series of great marine algal 

 floras: Phycologia Britannica, Phycologia Australica and the Nereis 

 Boreali Americana; he also described algae from many other parts 

 of the world, including New Zealand and Antarctica. In these 

 classical works on marine algae the plants were divided into Chloro- 

 spermae, Rhodospermae and Melanospermae. During the same 

 period Kiitzing (Kuetzing) in Germany was describing more new 

 genera than anyone either before or after. These were pubHshed in 

 a number of works : Systema Algarum, Phycologia Generalis and the 

 Tabulae Phycologicae. At the same time Braun was studying repro- 

 duction in algae and he has since been remembered for his con- 

 tributions to the sexual reproduction of the Charales. However, 

 work on the algae was still largely restricted to taxonomy, very 

 little having been done on life cycles and nothing on their ecology 

 or physiology. 



The discovery of salt deposits in the nineteenth century caused a 

 major recession in the kelp trade in France and Scotiand, but with 

 the discovery of iodine, coupled with the fact that the marine algae 

 were rich in it, the kelp trade received a new lease of life towards 

 the end of the century. This was not long-Uved because of the 

 discovery of iodides from which iodine could be extracted more 

 readily. By the turn of the century, therefore, the kelp trade was 

 once more in the doldrums. 



Towards the end of the nineteenth century a new group of 

 workers came to the fore, Areschoug (1866-84) described new 

 genera and species, but he also investigated zoospore and gamete 

 formation in Urospora (p. 83) and Cladophora (p. 84) and carried 

 out morphological studies in Laminaria (p. 172) and Macrocystis 

 (p. 186). This period can best be regarded as one devoted to re- 

 arrangement of the existing algal classifications. The information 

 that was accumulating, both about morphology and reproduction, 

 forced workers to reaUze that the old classifications were thoroughly 



