Plant Distribution. 
67 
OCCASIONAL NOTES. 
Plant Distribution. 
The Third Tanganyika Expedition. 
In Nature of January 25th appears a brief account by Mr. 
W. A. Cunnington of his recent expedition to Lake Tanganyika, 
undertaken largely in order to ascertain whether the botanical 
evidence bears out the striking conclusions arrived at by Mr. J. E. S. 
Moore on geological and zoological grounds. 
Water weeds, algae and phyto-plankton were collected from 
Nyassa, Tanganyika and Victoria Nyanza. Of the first named we 
are told that the Tanganyika forms appeared to differ but little from 
those collected in Nyassa. 
The working out of the collections will be awaited with much 
interest. 
Plants of the Seychelles. 
In the same issue of Nature there is an interesting letter from 
Mr. Stanley Gardiner on his recent visit to the Seychelles Archi¬ 
pelago. Little indigenous jungle remains in the islands, hut most 
of the trees are endemic species or genera. The more open spots 
in the forests have a dense undergrowth of Ferns, Lycopods, 
Selaginellas and Psilotum which cover also the lower parts of the 
trees. There is a comparative absence of herbaceous dicotyledons. 
The angiosperms shew a sharp distinction unto calciphilous, silici- 
philous and “indifferent” types, the last-named being a smaller 
percentage of the whole than either of the other two. Most of the 
calciphilous plants are identical with those of other coral islands 
visited and were probably ocean borne. 
Lodoicea seycliellarum has, according to Mr. Gardiner, two 
distinct, structurally different types of nut borne in about equal 
proportions on the same female trees. 
Mr. Guppy on Plant Dispersal, 
We have received from Messrs. Macmillan & Co. Mr. H. B. 
Guppy’s work, embodying his researches of more than twenty years 
on Plant Dispersal, particularly by ocean currents. We shall shortly 
publish a detailed review of this important work, but may note here 
one of Mr. Guppy’s main conclusions. He holds that the ivhole of 
the structural peculiarities which enable littoral seeds and fruits to 
float, are antecedent to the adoption of the floating habit, and are 
thus to be regarded as non-adaptive characters. 
