Cockayne — Plants of Chatham Island. 263 



white tomentum, as are also the short petioles and ultimate 

 branchlets. The epidermis is two-layered, and the vascular 

 bundles are surrounded by a sheath of stereome. 



Probably Sonchus grandifolius originally grew in some 

 abundance on the fixed dunes, bun at present it is to be found 

 only in a few places. Tetragonia trigyna also must at one 

 time have been more or less common. In one place on the 

 inland side of the dunes, near Lake Te Eoto, I noticed a few 

 plants of Dodoncea viscosa. 



Sand-covered Ledges on Bock. 



Closely related to the saud-dunes are those flat places and 

 ledges on maritime rocks on to which sand has blown. Eed 

 Bluff, on the west coast of Chatham Island, furnishes a good 

 example of the vegetation of such stations. There, just above 

 high-water mark, Sonchus grandifolius grows with great luxu- 

 riance, its large fleshy leaves pressed closely against the sand. 

 This plant is furnished with a very thick juicy creeping 

 rhizome. The leaves are of very great size, but unfortunately 

 I had no measure with me at the time of observation. 

 According to Mr. T. Kirk (37), they are -'from 1ft. to 2ft. 

 long by 4 in. to 7 in. broad." The plant is truly a herbaceous 

 one, its aerial portion dying down to the ground every year — 

 an uncommon phenomenon with the plants of New Zealand 

 generally. The young leaves make their appearance in Sep- 

 tember, and grow with considerable rapidity. The mature 

 leaves are thick and rather hard. The pale-green upper sur- 

 face is slighty concave, owing to the leaf-segments being bent 

 upwards ; the under-surface is glaucous, probably owing to a 

 covering of wax. The florets are pale-purple towards the 

 circumference of the head, assuming a lighter colour toward 

 the centre, where finally they are pale-yellow. The under- 

 surface of the florets is dark-purple near the apex. The outer 

 involucral bracts are extremely thick, and armed with short 

 thick spines. Such spiny bracts, with the addition of those 

 more internal, form an excellent protection to the young bud 

 which would otherwise be exposed to danger of injury from 

 the sand, often blown against it with great violence by the fre- 

 quent high winds. Growing in company with S. grandifolius, 

 and in considerable quantities, oxeApium australe, Samolus re- 

 pens. Salicomia australis, and the remarkable grass Agropyrum 

 coxii/-'- This latter forms large sheets lying on the sand. 

 It spreads by means of rather stout underground steins. Its 

 extremely supple filiform leaves are so much incurved as to 



* For the various new species mentioned, see further on, towards the 

 conclusion of the article. 



