58o A NATURALIST IN THE PACIFIC 



the pod that the wide dispersal of this beach-plant by the currents is due. 

 When experimenting on the freshly obtained seeds in Fiji I found that 

 four-fifths of them floated after three months in sea-water. With seeds that 

 had been kept for three years, half floated after twelve months and 

 retained their sound condition. The seeds owe their floating power to the 

 buoyant kernel. 



(2) Sophora chrysophylla. Seem. — The dry pods of this Hawaiian 

 mountain species float between one and two weeks in sea-water, but being 

 brittle they readily break down and the seeds escape. The seeds have no 

 buoyancy even after drying for four years. 



(3) Sophora tetraptera. Ait, from the coast of Chile. — After floating 

 from ten to fourteen days in sea-water, the dry pods become sodden and 

 begin to break up, the seeds escaping. Since, however, the pods tend to 

 decay and break open on the tree they would not be available for dispersal 

 by currents. Out of a number of freshly gathered seeds all floated 

 buoyantly after a month in sea-water, when the experiment ended ; and 

 of seeds that had been kept over a year six out of ten floated after four 

 months in sea-water, two of them germinating afterwards in soil. Like 

 those of S. tomentosa the seeds possess buoyant kernels to which the 

 floating power is due. On account of the hardness of the tests the seeds 

 to ensure rapid germination require to be filed. 



NOTE 57 (page 153) 

 On the Species of Ochrosia 



Schumann distinguishes the following species : 



(a) O. parviflora, Hensl., widely spread in the Pacific islands. 



{b) O. compta, Schumann, confined to Hawaii and corresponding to 

 var. B. of O. sandwicensis as given by Hillebrand. 



{c) O. borbonica, Spr., synonym O. oppositifolia. Lam., from Mauritius 

 and Madagascar to Java and Singapore. 



„ J O. sandwicensis, Gray, of Hawaii. 1 Botn probably varieties of 



^ ' I O. elliptica, Lab., of New Caledonia. J O. borbonica. 



(«) O. parviflora, Schumann, of New Guinea, probably identical with 

 O. mariannensis. 



NOTE 58 (page 156) 

 On Pandanus (from Warburg) 



(a) Tke size (lengtJi) of the drupes of endemic species in oceanic islands. — 

 The drupes of P. reineckei of Samoa are 4-5 cm. (if-2 inches). Those of 

 P. joskei and P. thurstonii in Fiji measure respectively 6 cm. (zf inch) and 

 2\ cm. (i inch). 



Out of about sixteen species in the Mascarene Islands (Mauritius, 

 Reunion, and Rodriquez) quite half have drupes 2-3^ cm. (^-if inch) 



