Chap, viii.] FOSSIL WOOD. 169 



hills just above it, at Mutton Cove, were quite free from snow 

 at the time of our visit. 



In a pool of water, on the summit of Table Mountain, I 

 found a quantity of specimens of a small Luiuhriculus, or allied 

 form of Annelid. 



The phonolith of which Table Mountain is composed, is full 

 of olivine crystals, occurring in large rounded masses as in the 

 Ardeche valley, and many other volcanic districts. 



A comparatively low ridge separates the head of Christmas 

 Harbour from the sea directly beyond. On a flat expanse of 

 this ridge are two .small freshwater lakes, in which grow two 

 water plants, Liinosella acjiiatica and Nitella antardica, both 

 widely spread plants, the first occurring, amongst other places, 

 in England ; and the second being very closely allied to a 

 common English species. 



I found LimoseUa aquatica only in these particular lakes, 

 and then only after a very long search, since it resembles 

 extremely closely, in its general appearance, when growing in 

 masses, a Rajuiiicuhis {R. Mosekyi, Hk.f.), which grows with 

 it in the water. 



Above the lakes the ridge rises somewhat, and then ter- 

 nn'nates in an inaccessible precipice fronting the sea, with short 

 talus slopes below, on which are rookeries of crested penguins. 

 Under the peculiar overhanging rock, on the south of the har- 

 bour, are beds of fossil wood, and the excavation beneath its 

 base is hence called Fossil-wood Cave. The wood occurs in 

 beds lying nearly horizontal, and a few feet only in thickness. 



The beds are of a soft whitish clay-like matter, which is 

 full of black vegetable remains, all apparently so charred and 

 decomposed as to give little or no hope of any structure being 

 made out in them. 



The wood is in large trunk-like masses ; the largest which I 

 saw was about \\ foot in diameter; in some the bark is pre- 

 served. The wood is in various states of fossilization, some 

 of it being comparatively soft, other specimens extremely hard, 

 passing even in the centre into actual basalt, containing small 

 amygdaloidal masses of zeolites. Analcite and other zeolites 

 are abundant in the Kerguelen lavas, as are also agates.* 



On the talus slopes beneath the cliffs, along the whole south 

 side of Christmas Harbour, are vast Penguin rookeries ; the 

 Penguins here nesting amongst the stones where vegetation is 

 entirely wanting : and to the north of the harbour at its entrance 

 are other similar rookeries. Towards the upper part of the 

 harbour, the rookeries are those of the smaller crested penguin 

 called " Rock-hopper " by the sealers {Eudyptes saitafor), the 

 * .See J. Y. Buchanan, " Proc. R. Soc," No. 170, 1876, p. 617. 



