Cockayne. — Observations on Coastal Vegetation. 313 



1. Introduction. 



Tn this series of papers no attempt will be made to give a 

 detailed description of the whole coastal vegetation of the South 

 Island. This introductory paper is purposely quite general, 

 and intended chiefly to pave the way for future work, and to 

 save repetition when dealing with the formations themselves. 

 As for these latter, only those ^vill be described which I have 

 had some special opportunity of examining during the last few 

 years. Each account will treat of some special part of the coast, 

 and be complete in itself, therefore no classificatioti of the for- 

 mations vnW be attempted, nor any such presentation of them 

 in a comiectcd sequence as would be necessary were the co-istal 

 vegetation of the South Island as a whole the theme. The 

 treatment of the formations, too, M'ill be far from exhaustive. 

 Such can only be expected from local botanists. Some attempt, 

 however, will be made to give a word-picture of each formation, 

 and details will be furnished regarding the conditions under 

 which such exists, while something wU be said as to the life- 

 forms of the most important constituents. As in my former 

 phytogeographical papers, the term "formation" is adhered to 

 on the score of priority,* while that of " association " is re- 

 stricted to those smaller combinations or groups of plants which 

 are frequently clearly defined mthin a formation. f 



At the conclusion of this paper ^ are included, in the Bibho- 

 graphy, the names of the more important papers referring to 

 my subject. It must, however, be pointed out that these 

 usually contain but little matter of ecological interest, and that 

 for the most part they are lists of plants. In fact, so little has, 

 up to the present time, beeii published regarding the coastal 

 vegetation of the South Island that I do not consider it neces- 

 sa.ry to give a summary of our knowledge on the subject. 



Properly speaking, the South Island of New Zealand does 

 not form a distinct phytogeographical pro^dnce. Strange as 

 it may seem. Cook Strait forms no line of demarcation between 

 the North Island and the South Island floras — so far. at any 

 rate, as the lowland region is concerned. It is not until lati- 

 tude 42"{ south is reached that the South Island vegetation 



* See, on this head, Olsson-Seffer, P., " The Principles of Phyto- 

 geographic Nomenclature," Bot. Gaz., vol. xxxix, p. 183 (1905). 



t Such are now clearly recognised by many ecologists — e.g., Ganong, 

 W. R, Bot. Gaz., vol. xxxvi, pp. 301, 302 (1903); Harshberger, J. H., 

 ibid., p. 372 ; Smith, W. G., Scot. Geol. Mag., vols, xx, xxi, p. 020, p. 20. 

 This latter botanist also u.ses the term " sub-association." 



X Latitude 38° south forms a much more natural floral boundary, 

 to the north of which lies the " northern province " of New Zealand, as it 

 may be called, while from 38° south to 42° south is the " central province," 



