292 BOTANICAL NOTES. 



beans (species of Mticuaa, Ccmavalia, Dloclea), the long germinated 

 seeds of the mangrove (Rhizophora), an occasional cocoa-nut, the 

 cones of Casuarina equisetifoUa, Terminalia catappa, Lumnitzera 

 coccinea, Guettarilx speciosa, Ochrosia parvifiora, Iler'itiera Uttoralis 

 and others.^ 



The foregoing seeds and seed-vessels with many others may be 

 ob.served washed up by the waves on the surface of the bare sandy 

 islets or sand-keys, which exhibit the first stage in the growth of 

 those picturesquely wooded coral islets that are ultimately formed 

 on the reefs. On such a sand-key, not more than some 25 or 30 

 yards across, I have counted as many as 30 different kinds of seeds 

 and fruits, all collected together in the centre, which was only 

 washed over at spring-tides. One of tlie first trees to establish 

 itself is the mangrove {Rldzophora), which by its reclaiming agency 

 adds to the area of the islet and enables other trees, such as Lum- 

 nitzera coccinea, to take up their abode. Pari passu with the sea- 

 ward extension of the reef, the islet increases in size ; and in time 

 the winds and currents bringf other fruits and seeds which germi- 

 nate and form ultimately the belt of littoral trees bordering the 

 beach. In this manner Barringtonia speciosa, Calophyllibm inophyl- 

 ■lum, Thespesia populnea, Hibiscus tiliaceus, Cerbera odollam, Ochrosia 

 parvifiora, Heritiera Uttoralis, Terminalia catappa, different species 

 of Paadanus, Casuarina equisetifoUa, and Gycas circinalis with many 

 others referred to on a previous page, become established. It is 

 worthy of note that the fruits of the great majority of trees which 

 form the maro;in of the vecjetation, whether on the lee or weather side 

 of such an islet, float in salt water.^ The small cones of the Casuarina 

 however, require a certain amount of drying before they can be 

 transported by the waves. The green fruits of the Cycas usually 

 sink in salt water ; but I found that one out of ten specimens 

 floated, an exceptional circumstance which sufficiently accounts for 

 the occurrence of Cycas circinalis on these coral islets. 



Whilst through the agencv of the winds and currents the waves 

 have stocked the islet with its marginal vegetation, the fruit pigeons 

 li.ave been unconsciously" stocking its interior with huge trees, that 

 iiave sprung from the fruits and seeds they have transported in 

 their crops from the neighbouring coasts and islets. Perched up in 



1 Other fruits found floating were a second species of Calophyllum, a species of Gom- 

 ihranda, HarimUia sp., and some Scilamiacce. 



- Tlie results of some experiments I made are given oy page 305. 



