XXX BRUGUIERA 461 



the plumule against being scorched in the sun, it increases consider- 

 ably the risk of injury from direct impact. 



As bearing on their capacity for dispersal in other fashions, it 

 may be remarked that Rhizophora seedlings can withstand long 

 drying. Five which had been kept dry for nine weeks, after having 

 been found stranded on a beach, were planted in the mud of a 

 mangrove-swamp. In a fortnight two of them were developing the 

 first leaves and throwing out roots. As long as they are protected 

 by a covering of vegetable dSbris and sand, the stranded seedlings 

 might retain their vitality for months. 



Bruguiera rheedii (Blume) 



This species is reduced in Hooker's Flora of British India to 

 Bruguiera gymnorhiza (Lam.), and thus viewed it has a very wide 

 range in the Old World, corresponding very much to that of 

 Rhizophora mucronata, namely, tropical East Africa, tropical East 

 Asia to the Liukiu Islands, the Indian Archipelago, New Guinea, 

 tropical Australia, and Western Polynesia, as in New Caledonia, 

 Fiji, Tonga, and Samoa. There are four or five species of the 

 genus, but all are confined to the Eastern Hemisphere, none 

 occurring in America. 



As with the species of Rhizophora, this plant is indebted for its 

 present dispersal to the floating seedling, which, however, often falls 

 from the tree whilst still attached to the fruit, but is generally freed 

 in a day or two. The seedlings float for a long time in sea-water. 

 I kept one of them afloat for 117 days, when it was quite sound and 

 healthy. They appear to be better fitted than the species of 

 Rhizophora for the " rough-and-tumble '' of ocean transport, since 

 the plumule is much less prominent, projecting only one line 

 (2'5 mm.) or less, whilst with the two Fijian species of Rhizophora 

 the plumule measures from seven to twelve lines (18 to 30 mm.). 

 In the latter part of the year they are to be found in abundance in 

 the floating drift of rivers, and there they readily develop the first 

 leaves and roots. They are also frequent in the sea off" the coasts, 

 and they are stranded in large numbers on the beaches, where they 

 readily strike into the sand when partially buried amongst the 

 vegetable drift. 



The empty flowers and the germinated fruits containing the 

 cotyledons are very common in floating drift. They look much 

 alike, but the flowers are much smaller and possess the long style. 



