178 DR. G. DICKIE ON 8T.-HELENA MARINE ALGA. 
On the Marine Alge of the Island of St. Helena. 
By G. DrcxiÉ, M.D., F.LS. 
[Read March 7, 1872.] 
THERE is a very excellent summary of the land.plants of St. 
Helena in Dr. Hooker's lecture delivered at the Meeting of the 
British Association at Nottingham in 1866. The original plants 
are almost extinct; and, from what is known, the inference is, 
“it resembles none other in the peculiarity of its indigenous 
vegetation, in the great rarity of the plants of other countries, 
or in the number of species which actually disappeared in the 
memory of living man." Of the forty-five indigenous species, 
forty are absolutely confined to the island, and no fewer than 
seventeen have been referred to peculiar genera. As to the 
affinities of the flora, it is regarded as an African one, and cha- 
racteristic of Southern Extratropical Africa. 
I am not aware of any previous notice of the marine Alg:e of 
this interesting island ; and although the present list may not 
comprehend all the species, I have thought that, in the mean time, 
those known may be worthy of record. 
I am indebted to Mr. J. C. Melliss for the materials, having, 
at his request, undertaken to name the Alge collected by him. 
In a note he stated, * the collection includes all that grow on 
the coast of St. Helena; at least, they are all I could find: it is 
just possible some few small species may have escaped my notice, 
though I searched carefully. There were no large olive-coloured 
Alge on the rocks; and the species are difficult to find, because 
there is no tide beyond 2 feet 6 inches. The rock is volcanic, 
being basaltie lava; there is a strong current from the south- 
ward, it comes right on from the Cape of Good Hope." 
I. MELANOSPERME E *. 
Family DrervoraAcE x. 
Padina pavonia, L. 
Geographical Distribution:—South Britain, France, &c., United 
* Mr. Melliss sent me the root and part of the stem of a large species 
several feet in length, which comes on shore in a battered state on the southern 
side of the island; from structure I believe it to be Eclonia buccinalis, a well- 
known Cape species, and doubtless drifted from that quarter. 
