26 
Ridley. — The Distribution of Plants. 
Mascarene Islands along the coasts of India ( Tournefortia , Ceylon and 
Andamans only), through the Malay region to Polynesia. Both are very 
scarce in the Malay Peninsula, though abundant in the Malay Islands, 
because they both grow on raised coral-reefs and there is practically no 
raised coral-reef in the peninsula. 
The following maritime plants, besides the above mentioned, occur all 
over the tropics in both hemispheres: Caesalpinia Bonduc , Roxb., and 
C. Bondncella , Flem. (Leguminosae), Iponioea biloba , Linn. (Convolvulaceae), 
Hibiscus tiliaceus , Linn., Sid a cordifolia , Linn., .S', rhombifolia , Linn., 
A. carpinifolia , Linn. (Malvaceae) (these Sidas are also weeds of cultiva¬ 
tion), Cassytha filiformis , Linn. (Laurineae), Fimbristylis spathacea , Roth., 
Remirea maritima , Aubl. (monotypic Cyperaceae), P asp alum vaginatum , 
Sw. (Gramineae). All except Remirea and Cassytha belong to genera of 
many species of inland plants, none of which has anything like their 
distribution. Many other maritime plants have an area of the Mascarene 
Islands and all Asiatic coasts to Polynesia, but have not reached or settled 
in America. In all cases the story is the same ; they are far more widely 
distributed than their inland non-maritime allies. 
It is in the highest degree improbable that the inland species of these 
plants, numerous as they often are, can be derived from the few or solitary 
maritime species, but on the contrary the maritime species, retaining the 
general form of the fruit modified for sea-dispersal, must be derived from 
one or other species of the inland ones ; consequently the widest distributed 
species must be later in time of evolution than the local and often endemic 
species. 
Bird-carried Seeds. 
There are a number of widely distributed plants which inhabit swampy 
ground and edges of ponds and open streams, but which do not appear to 
be weeds or to have been helped in any way by man. They chiefly con¬ 
sist of Cyperaceae. Such are Rhynchospora aurea , Vahl., R. glauca, Vahl., 
Cypertts Haspan , Linn., C. radiatus , Vahl., C. digitatus , Roxb., Eleocharis 
fistulosa , Schult., E . variegata , Kunth., E. capitata , Br., and Polygonum 
hydropiper , Linn. From the way in which most of these plants appear 
on the edges of artificial ponds, where the sandpipers often alight 
after their long migrant flights, I should suggest that these waders bring 
them in their feathers or possibly attached to their feet. Most have quite 
small seeds which could be easily carried in this way, but Guppy has shown 
that Cyperaceous seeds can be successfully carried by ducks in their 
intestines, and Polygonum seeds by various other birds in the same way. 
The Jussiaeas (Onagraceae) seem to be carried about largely by water-fowl, 
as they have the same habitat, but the American species, though closely 
allied to the Asiatic ones, appear to be specifically distinct. 
