144 TRINCE EDWARD ISLANDS. 



The rocks, about high-tide mark, are covered with a dense 

 growth of the large brown seaweed, D' Urvillcea utilis, which is 

 of great assistance in breaking the surf. Beyond the ordinary 

 reach of the sea, but still within the beach-line, the rocks are 

 covered with a crassulaceous plant {Tilkca vioschata, D.C.), 

 occurring also in Kerguelen's Land. Succeeding the beach is 

 a thick growth of herbage investing a swampy black peaty soil, 

 which covers the underlying rock more or less thickly every- 

 where on the lower ground and extends up with the herbage 

 almost to the snow. The principal plants forming the thick 

 growth are an Accvna (Aaena ascendetis), Azorella selago, and 

 a grass {Poa Cookii, Hk. f.). The Accena is by far the most 

 abundant plant on the island. 



The Azorella forms low, convex, bright green patches in 

 intervals between the AaT7ia or cake-like masses at its 

 roots. 



Azorella selago is a characteristic plant of the southern 

 islands, and will be frequently referred to in the sequel. It 

 belongs to the Umbellifer^e. It forms large convex masses 

 often several feet in diameter, which are compact and firm, and 

 when on solid ground yield little to the tread. The masses are 

 made up of the stems and shoots of the plants closely packed 

 together side by side, their flowering tips and small stiff and 

 tough leaves forming an even rounded surface at the exterior, 

 being all of the same length. The interior of the masses is 

 full of dead leaves and stems. The whole where growing in 

 abundance forms sheets and hummocks which invest the soil 

 for acres in extent with a continuous elastic green coating. 

 An allied plant, Bolax glebaria, forms similar masses at the 

 Falkland Islands, and there is a tendency in many Antarctic 

 plants to assume a similar habit, as in the case, e.g., of Lyallia 

 kerguelensis. 



The grass is abundant everywhere, mingled with the Acana 

 and Azorella. The plants are, no doubt, rendered especially 

 luxuriant by the dung of the numerous sea-birds ; but no mutual 

 benefit arrangement has sprung up between the Poa and the 

 penguins, as it has at the Tristan da Cunha group between the 

 penguins and Spartina arundinacea. The Poa Cookii nowhere 

 forms a tussock. The rookeries of King Penguins are entirely 

 bare, and the grass is not more luxuriant around the nests of 

 the Golden-crested Penguins than elsewhere. The Poa was 

 the only grass found in flower in the island. Different-looking 

 forms were observed, especially around the numerous pools of 

 water on the hill slopes ; but they are possibly mere modi- 

 fications of the same grass due to alteration of conditions ; 

 none of them were in flower. Pringlea antiscorbutica, the 



