Cross. — Ohservations on some New Zealand Ilalojihytes. 545 



Art. L\'II. — Observations on some New Zealand Halophytes. 

 By Miss B. D. Cross, M.A. 



[Bead before the Philosophical Institute of Canterbury, \st September, 1909.] 



Introductory. 



During tlie last liundred years there has been published an ever-increasing 

 volume of literature on the so-called halophytes — that is, plants occupying 

 situations where there is a superabundance of salt in the soil. This special 

 group of plants has been studied from all points of view — morphologically, 

 anatomically, physiologically, and ecologically. 



To some extent tliis order is chronological, for the first observers gave 

 their attention to external characters only, anatomical characters being 

 considered at a later date, while the ecological aspect has been the subject 

 of more modern papers. The physiological section of the subject still opens 

 up much field for research. At the very outset it is yet a debatable point 

 whether halophytes are to be considered salt-loving or salt-endviring plants. 



Historical. 



According to Lesage (ii, p. 6),* as early as 1804 an article on maritime 

 plants appeared in " L'Encyclopedic," where it is noted that such plants are 

 usually succulent, and have closely packed tissues {tissu serre). After this 

 date, and until the publication of his own book, Lesage considers that the 

 works of the following authors are the most noteworthy : Moquin-Tandon 

 (1841), Willkomm (1852), Lecoq (1854), Duval-Jouve (1875), Vesque, and 

 Prillieux ; and among these he gives the first place to that of Duval-Jouve. 



Before the appearance of Lesage's thesis, however, came the work of 

 Constantin " La Flore du littoral." f M. Constantin notes more especially 

 the external variations of maritime varieties, though he says that " It is 

 very probable that anatomical study will reveal modifications even where 

 the outward appearance would not lead one to suspect so." 



The works which have been most consulted for the compilation of this 

 paper, and more especially for the anatomical part of it, are those of Lesage 

 (ii) and Warming (v and viii), though several shorter papers by American 

 wTiters were found very useful for comparison (see bibliography, p. 574). 



Of New Zealand authors, Cheeseman (xvii) has been found invaluable 

 for identification of species. The New Zealand halophytes, however, have 

 been very much neglected, for, with the exception of a recent paper of 

 Dr. Cockayne's on " The Coastal Vegetation of the South Island of New 

 Zealand " (xix), there has been no special work on this part of the flora. 



Scope op the Paper. 



In the present paper it is proposed to deal with certain typical halo- 

 phytic formations in the neighbourhood of Christchurch, and to compare 

 these with similar formations at Timaru. 



* The numbers refer to the bibliography, page 574. 

 t Jour, de Bot., P^ annee. No. 3, p. 4-4, 1887. 

 18— Trans. 



