AN ACCOUNT OF THE SPECIES OF PORPHYRA 



FOUND ON THE PACIFIC COAST OF 



NORTH AMERICA. 



BY HENRI T. A. HUS. 



CONTENTS. 



Plates XX-XXII. 



I. History i73 



II. Morphology 175 



III. Distribution 192 



IV. Description of Species 195 



Key to the Pacific Coast Species 195 



V. Economic Uses .^ 230 



VI. Methods 231 



Literature and Exsiccate Cited 234 



Explanation of Plates 236 



I. History. 



From a systematic point the genus Porphyra has been 

 scantily dealt with. Created in 1824, by C. A. Agardh, to 

 contain those species of " 6Vz^«" which possess a red color- 

 ing matter, it has since been fully treated by but two 

 authors— J. G. Agardh (1882) and J. B. de Toni (1897). 

 The former author was the first to distinguish between 

 monostromatic and distromatic species. This idea was car- 

 ried still farther by Kjellman, who in 1883, in his "Algae 

 of the Arctic Sea," distinguished between the genus Por- 

 ■phyra and the subgenus Dipio derma, the latter to include 

 all distromatic species. 



The name Diploderma was changed by de Toni (1897) 

 to Wildeman ia . 



L. Kolderup Rosenvinge (1893) used the name Por- 

 -phyra for both monostromatic and distromatic species, 

 retaining Diplodernia as a subgeneric name. This appears 



* Contributions from the Botanical Laboratories of the University of Cal- 

 ifornia and presented in partial fulfillment of the requirements for the degree 

 of M. S., May, 1899. Prepared under the direction of Professor W. h. Setchell. 



[173] December 14, 1901. 



