156 
WILLIS AND GARDINER ; BOTANY 
are Cycas, Pandanus spp., Heritiera littoralis, Terminalia 
Catappa, Cerbera Odollam, &c. Further inland are large 
banyans, and other trees introduced by birds. 
Under the descriptions of the various islands and atolls 
above given many interesting details are recorded as to the 
composition of the floras, and the appearance of pJants on 
newly formed reefs or the flora of those which are wash- 
ing away. The main general features only are summarized 
below. The flora differs considerably according to whether 
the island in question is rocky or sandy. In each case the 
more strictly littoral flora may be perhaps subdivided into 
the beach jungle and the shore herbs. 
When a new bank forms, the vegetation brought to it is 
at first all sea-borne, but after a few shrubs appear the 
islet is visited also by birds, bringing other species with 
them. The order of appearance of plants was studied in 
Mahlos {q.v.) on a number of islets, and confirmatory 
observations were made elsewhere. The first arrivals are 
in general Launæa, Spinifex, Mariscus Dregeanus, Eragros- 
tis plumosa, Aerua lanata, Tournefortia argentea, Suriana, 
and Scævola. The last-named is often late in coming, but 
spreads with great rapidity when once established, and 
largely at the expense of the Tournefortia, which, at first 
numerous, is often only represented after some time by a 
few clumps or isolated trees. On the first shrubs Cassytha 
filiformis is nearly always to be seen, presumably brought 
by birds. The islets are visited by waders, terns, herons, 
&c. Thus on a young sandy islet, both a shore herb forma- 
tion and a beach jungle are soon formed. The former lies 
further out than the latter, and corresponds very much to 
the Ipomœa Pes-capræ formation of Schimper (lx. 77). 
Ipomoea biloba (I. Pes-capræ) itself is rather rare in the 
Maldives. The beach jungle of the sandy island is not so 
complex as that described by Schimper as his Barringtonia 
formation, but resembles it in general. Ochrosia borbonica, 
Terminalia catappa, Morinda citrifolia, and the small species 
