Chap. V.J VEGETATION OF THE TRISTAN GROUT. 11/ 



contains a Pelargonium and an abundance of both the Phylica 

 and Spartina of Amsterdam Island, together with species of 

 Oxalis and Hydrocotyle. The Fuegian and Falkland Island 

 plants of Tristan da Cunha and its islets, which have not 

 hitherto been found in the islands south and east of them, are, 

 however, more numerous than the Cape genera even, and 

 include Card a mine hirsuta, Nertera depressa, Empetrun nigrutft 

 var. riibrum, Lagenophora Commersoniana, and Apium australe ; 

 and the flora contains besides the strictly American genus 

 Chevreulia." 



The close similarity of the flora of the three islands of the 

 group points to a former connection between them. Their 

 high cliffs, composed of successive layers of lava, and the 

 absence, except in Tristan da Cunha, of well marked centres 

 of eruption, as well as their general features, show that they 

 have undergone great denudation. A sounding between Tristan 

 da Cunha and Inaccessible Island gave a depth of i,ooo 

 fathoms ; between Inaccessible and Nightingale Islands, the 

 depth was 460 fathoms. 



It is obvious, from the relative position of the three islands, 

 that the prevalent winds blow directly from Inaccessible island 

 towards Nightingale Island and Tristan da Cunha. 



With regard to the Cryptogamous vegetation of the group, 

 nearly all the seaweeds, as appears from Prof. Dickie's report 

 on the specimens collected by me, are Cape of Good Hope 

 species, or occur at the Cape as well as at numerous other 

 localities : two only are new and apparently endemic. Of 

 Fungi, an Agaricus, which grows on the Phylica stems, is 

 described by Mr. Berkeley as new, as A. phylicigena. Of the 

 mosses and Hepatiae, Mr. Mitten describes ten species as new, 

 out of thirty-six collected by me ; of eleven lichens collected, 

 two were new ; one, Lecanora acunhana, is noted by Nylander 

 as " bene distincta." 



An Islander told me that the flowering plants on Gough 

 Island were the same as those of Tristan da Cunha, but he 

 thought there were different ferns ; he had lived there some 

 time sealing. 



Scientific Notices of the Tristan da Cunha Group. 



Du Petit Ihouars, flora of the island, in his "Melanges." 



Captain Carmichael's account of the island in " Linn. Trans.," Vol. XII., 

 p. 496. 



For descriptions of the collections of plants made by me in the Islands, 

 see list of papers relating to the " Challenger " Expedition, at the end of 

 this Book. 



For a description of Gallinula nesiotis, by P. L. Sclater, F.R.S., etc., 

 see " Proc. Zool. .Soc, 1855,"' p. 146. 



