274 Mr George Traill on the 



The Marine Algce of the Dunhar Coast. By George 

 W. Traill, Joppa. 



(Read 9th January 1890.) 



The coast of Dunbar is one of the richest localities for 

 Marine Algae in the Firth of Forth. 



Though the species, so far as at present known, are less 

 numerous than those occurring on the coast of Elie, the plants 

 are generally luxuriant and, in many cases, of larger growth. 



Owing, probably, to the depth and purity of the water, 

 Laminaria hyperhorea is unusually abundant ; and, con- 

 sequently, many deep-water Algse which are generally 

 epiphytic on this plant, and seldom met with at any great 

 distance up the estuary of the Firth, are here of frequent 

 occurrence, and often fine as specimens. 



On account of the numerous pools between tide-marks, 

 and owing to the rocky shores being intersected with many 

 creeks and crevices affording every variety of light and shade, 

 the species belonging to the littoral zone are also fairly well 

 represented, and are almost as remarkable for their luxuriant 

 growth as those occurring in deep water. 



Near the " Vault," at Broxmouth Point, there is an exten- 

 sive rocky platform sloping down gradually towards the sea. 

 This place, besides being fertile in species, is most instructive, 

 as it illustrates in a remarkably clear way — often in sharply 

 defined zones — the particular Algse applicable to each suc- 

 cessive level. 



In the following list I have given the habitats of the Algfe, 

 and, in the cases of the rarer species, their exact localities ; 

 also their usual life periods, and seasons for fructification. 

 The dates are necessarily approximate in some cases, as they 

 vary according to the climatic influences of different years. 



Where the species is epiphytic on other Algse, a list of 

 the most usual host plants is given, and the order in which 

 they are mentioned expresses their respective numbers. 



In another paper * I have endeavoured to show, from 

 numerous examples, that the epiphyte, or parasite, by some 

 process of natural selection, invariably attaches itself to a 



* "The Parasitical Alga' of the Firth of Forth," read before the Royal 

 Society ol Dubli.1, Apiil 1882. 



