246 Transactions. 



Art. XXIX. — Notes on the Plant-covering of the Breaksea Islands, Stewart 



Island. 



BjJ). L. POPPELWELL. 

 [Eead before the Otago Institute, 7th September, 1915.] 



The Breaksea Islands consist of a group of six small islands lying on the 

 east of Stewart Island, between Port Adventure and Lord's Kiver. Their 

 latitude is 47° 6' S. and longitude 168° 15' E. As the eastern coast of Stewart 

 Island trends away towards the south-west from this latitude, these islands 

 receive no protection from the southerly weather, which strikes and breaks 

 on their southern sides with full force ; hence the name of the group. On 

 the 7th January, 1915, by the kindness of Mr. Henry Hansen, I had the 

 good fortune to be able to visit the principal islands of the group, and take 

 some notes of their plant-covering. 



Comparatively little has been recorded of the botany of these outlying 

 islands ; therefore a short description of their plant associations may be of 

 interest, 



EUKAWAHA-KURA, OR JoSS's ISLAND. 



This is the largest of the group, and lies only about 500 m. from the main- 

 land of Stewart Island. It was the first one visited by me, and some time 

 was spent in examining its vegetation. The island is almost circular in 

 shape. It is not more than about 50 m. high, and is about 500 m. in 

 diameter in its widest part. There is a good landing on the north-east side. 



The plant formations are best considered under three heads— namely, 

 (1) rocks and cliffs ; (2) forest ; (3) heath. 



(1.) Rocks and Cliffs. 

 Most of the coast-line of the island consists of steep rocky faces, covered 

 from above high-water level with a close association of almost pure Olearia 

 angiistifolia where there is sufficient soil to give it a hold, but in other 

 places with Poa Astoni, which covers the cliff-faces with a grey -green drapery. 

 Here and there, where the wind strikes less directly, great green patches of 

 Stilhocarpa Lyallii, with their large leaves overlapping one another, can be 

 seen, giving quite a tropical appearance to the vegetation. On exposed 

 rocks Crassula moschata is plentiful, its reddish stems contrasting stronglv 

 with the greyish-white of the granitic rock. At the rear of the frontal 

 rocks the shore ferns Asplenium obtusatum and Blechnum durum are abimd- 

 ant, the former in more or less isolated clumps and the latter in large 

 closely matted patches. On the cliff-faces Olearia Colensoi is plentiful, 

 especially behind the fringe of 0. angiistifolia ; while Veronica ellipttica, 

 although a little past full flowering, still gave by its bloom a whitish tinge 

 to the cliff-side, especially where the soil is deepest. Occasionally Draco- 

 phyllum longifoliuni pushes its brown head through the other plants, espe- 

 cially where the stunted shrubs bear testimony to the power of the wind. 

 In parts of the island the cliff' vegetation also contained Mesemhnjanthemum 

 australe and Tetragonia trigyna, both plants giving a warm colour to the 

 association, the former by its bright-pink flowers and the latter by its 

 reddish leaves when exposed to extreme light. At a short distance away, 

 however, the most dominant feature of the sloping cliff-covering is Olearia 

 ■ angustifolia, which is the principal plant in exposed situations. It protects 



