222 Marine Algce of Berwick-on-Tweed. 



preparing the present list which, with the exception of Diatoms, 

 is intended to include all the species of Marine Algae known to 

 occur betweeu Eyemouth aud Holy Island, I have taken Le 

 Jolis's "Liste des Alyues Marines de Cherbourg," and Prof. 

 Farlow's '• Marine Algue of New Eugland," as my models, aud 

 have borrowed from them without reserve whatever was suited 

 to my purpose. 



I have given no description of those species described in 

 Harvey's " Phycologia Britannica " and "Manual," as to have 

 done so would have greatly added to the bulk of this paper 

 without materially adding to its usefulness. [ have, however, 

 under each species referred to a published description,* and in 

 most cases also to a figure of the plant named, and have added 

 an artificial key to the Genera, adapted, with Prof. Farlow's 

 consent, from the key given at the end of his " Marine Algae 

 of New England." The classification followed is, to some 

 extent, a modification of that adopted by Dr. F. Hauck in his 

 "Die Meeresalgen von Deutschland." The dates given for the 

 duration and time of fruiting are of course approximate only, and 

 referring solely to the seasons at which the plants are to be 

 met with at Berwick, would probably mislead anyone col- 

 lecting elsewhere. The genera Leptothrix, Beggiatoa, and Cohnia 

 (Clathrocystis) have not been included in this list, as they are 

 now, apparently with good reason, more usually classed with 

 Schizomycetes. 



For several years I have visited Berwick at all seasons for the 

 purpose of collecting, and with very few exceptions have myself 

 gathered every species recorded in this list. I would here 

 express my obligations to Mr E. M. Holmes for constant assist- 

 ance in the identification of species, and for valuable suggestions 

 as to what species were likely to occur at Berwick ; to Mr G. W. 

 Traill for particulars of the species found in the Firth of Forth, 

 aud consequently to be expected on our coast; and to Mr T. H. 

 Buffham, who has kindly taken measurements of many of the 

 species for me. I would also return my sincere thanks to Dr. 

 Edouard Hornet of Paris, whose kindness in examining aud 

 naming all the specimens about which I had any doubts has 

 enabled me to give to this list a degree of accuracy it could not 

 otherwise have possessed. I am also indebted to Dr. F. Hauck 



* Where possible t\iu reference is ti> ;i description in Ettylixh, 



