Clare Island Survey — Marine Algae. 16 13 



comparative purposes. For the Adriatic, we have Tecket's general account of 

 the algal vegetation of Trieste ('06). The Iceland marine algae are the latest 

 to receive . attention from the ecological standpoint, Jonsson's work ('10) 

 forming a useful addition to his systematic papers which appeared previously. 

 Outside Europe, Svedelius' paper on the periodicity of algae in Ceylon coral- 

 reefs ('06), Skottsberg's work in the Antarctic ('06), and Borgesen's accounts 

 of the algal vegetation of the Danish West Indies ('00, '01, '11) are 

 apparently the only papers of the kind which have appeared ; but reference 

 should be made to Weber van Bosse ('04), and Schiller ('09), which border on 

 the subject. 



Turning to the British Isles, with the exception of Battray's paper referred 

 to above, no account of the algal communities found on our coasts has 

 appeared, though, as will be seen later, a certain amount of autecology has 

 been done. The numerous and important additions to the British algal flora 

 recorded by Mr. E. M. Holmes and by the late Mr. E. A . L. Batters, have kept 

 our knowledge of the flora well up to date as far as its purely systematic aspect 

 is concerned. Ecological factors, too, were not disregarded, the " habitat " of 

 a species having been always given a prominent place by British writers ; so 

 much so, that in a few cases the specific distinction of similar plants has been 

 strongly advocated on the ground of a difference in habitat. Casual reference 

 to the " Eucus-belt," "Coral-banks," and " Laminaria-zone," shows that the 

 more obvious associations were not overlooked. 



Battray ('85) treats at some length of the size of individuals when gathered 

 from different localities and from different levels ; he also deals with various 

 problems connected with the distribution and development of the spores. 

 With regard to algal communities, he recognizes the " regions " of 

 Kjellmann, and describes a number of " areas " (" formations " of Kjellmann) 

 characterized by the presence of certain dominant species. His " areas," 

 whether littoral or sub-littoral, are classified almost entirely with reference 

 to vertical distribution, and there is no attempt to connect them with other 

 conditions such as exposure and desiccation. This results at times in a 

 curious association of names in a given zone, and renders the account some- 

 what obscure to anyone not familiar with the exact topography of the 

 locality. The paper is, however, full of facts, and will be of great interest 

 and value to the next investigator of the algal vegetation of the Firth of 

 Forth. 



In a memoir on GJiondrus crispus by Darbishire ('02), the general ecology 

 of the plant is dealt with, and incidentally reference is made to. the principal 

 zones of vegetation that occur on the shores of the Isle of Man. Two 



