166 Transactions. 



Art. XIX. — Notes from the Canterbury College Mountain Biological Station. 



No. 1. — The Principal Plant Associations in the Immediate Vicinity 



OP the Station. 



By L. Cockayne, Ph.D., F.L.S., F.R.S., and C. E. Foweraker, M.A. 

 [Read before the Philosophical Institute of Canterbury, 1st December, 1915.] 



Plates XV, XVI. 



(A.) GENERAL. 



In his general account of the Canterbury College Mountain Biological 

 Station, Dr. G. Chilton points out— Trans. N.Z. Inst., vol. 47 (1915), p. 333— 

 that when the boundaries of the botanical reserve are defined and surveyed 

 a botanical map of the area will be prepared. Such a maj) would, of course, 

 be based on the distribution of the florula as determined by that of the 

 plant associations. A classification and preliminary account of these asso- 

 ciations is, then, a necessary prelude to that detailed study which the pre- 

 paration of a map of the vegetation demands. The associations as defined 

 below, although the outcome, in part, of the great topographical changes 

 which have befallen the area during and subsequent to its period of intense 

 glaciation, are considered from the static and not from the dynamic stand- 

 point, since for purposes of graphic representation they are distinct vege- 

 tation entities for the time being. This viewpoint does not in the least 

 preclude the ultimate necessary study of the plant-covering with regard to 

 its evolution ; it merely offers a convenient basis for present investigations. 

 No attempt is made at thoroughness in our treatment of the associations, 

 which is descriptive merely ; nevertheless we believe that brief, incomplete 

 descriptions of undescribed plant communities are better than nothing, and 

 can be of considerable assistance to those engaged in comparative studies of 

 New Zealand vegetation. Each association is a collection of species bound 

 to a definite habitat, the latter being the sum total of the various ecological 

 factors to which the association is exposed. " Habitat,'' as thus defined, is 

 virtually impossible to determine accurately, but it is roughly measured by 

 climate, by the nature of the soil in its widest sense, by the relation of plant 

 to plant, and by the animals present. But, even were we able to estimate 

 the exact results of habitat, no such great advance wou^ld be made as might 

 be supposed, since each species exists under a distinct environment of its 

 own. Such individual environmental differences may, in fact, easily be 

 far greater within one association than are the general habitat-influences 

 of two adjacent distinct associations. 



The Canterbury College Mountain Biological Station is situated in the 

 Eastern South Island Botanical District,* close to its junction with the 



* The botanical districts referred to in this paper may be provisionally defuied 

 as follows : (1.) The North-eastern South Island Botanical District includes the north- 

 eastern portion of the South Island, excepting the wet area in the vicinity of the Marl- 

 borough Sounds, and it is bounded on the west by a line marking the average limit of 

 the western rainfall, and on the south by the River Waiau. (2.) The Eastern South Island 

 Botanical District is that area extending from the Waiau to the Waitaki Rivers, and 

 terminating on the west at the line reached by the average western rainfall. (3.) The 

 Western South Island Botanical District extends from the River Taramakau in the 

 north to a line not yet determined, lying somewhat to the south of the River Haast, 

 and on the east it crosses the actual divide and is bounded by a line marking the average 

 limit of the western rainfall. — L. C. 



