192 PLANTS, SEEDS, AND CURRENTS 



a shore plant, but it habitually extends far inland in the savannah- 

 like plains on the dry sides of the islands. It is, however, as a littoral 

 plant that it seems to be most frequently mentioned in the Old 

 World. In the Malay Peninsula, as we learn from Ridley, it is com- 

 mon in open sandy country near the sea (Trans. Linn. Soc. Bot., 

 III., 267; 1888-94). On the numerous coral islands of the Java Sea 

 it grows very luxuriantly, covering the woody and herbaceous 

 plants with a felt-like coat (Schimper's Plant Geogr., p. 341, and 

 Ind. Mai. Strand Flora, p. 188). It is stated below that after the 

 eruption Cassytha filiformis established itself among the strand 

 plants of Krakatau. As Prof. Scott Elliot tells me by letter, it 

 crawls over the low bushes and covers the surface of coastal sand- 

 dunes in Madagascar. In the West Indies this plant occupies 

 similar stations. Whilst it is characteristic of the savannahs and 

 lower woods of Jamaica, it is also found at the coast. Millspaugh 

 observed it trailing over the beach sand-dunes on Cayman Brae 

 and in similar situations on Porto Rico (Plant. Utow.). In the 

 Bahamas it grows over the shore plants and is found in the thicket 

 formation inland (Harshberger's Phyt. Surv. N. Amer., pp. 691, 

 693-4). In South Florida it is a plant of the coastal dunes and 

 of the east-coast pinelands (Harshberger, Trans. Wagner Inst. 1914, 

 pp. 70, 92, 93). Over the West Indian Islands this parasite is 

 widely distributed, and it ranges in the New World from South 

 Florida and Mexico to Brazil. 



In the Pacific Islands I found that its small fruits, whether from 

 coast or inland plants, were able to float unharmed in sea-water 

 for months. On the other hand, fruits obtained by me from the 

 moist lower woods of Jamaica displayed no buoyancy, even after 

 being kept for years, the unfilled space in the fruit-cavity to which 

 the floating power is due being absent in this case. The floating 

 capacity is probably as a rule developed in stations where xerophytes 

 thrive, as on the coast and in savannahs. 



From its frequent station at the coast, and from its occurrence 

 in small coral islands, it cannot be doubted that the currents take 

 advantage of the buoyancy of the fruits to disperse the plant. As 

 long ago pointed out by Schimper frugivorous birds would also aid 

 in the distribution, the fruits in the moist condition being likely 

 to attract birds. In fact, fruits have been found in the crops of 

 pigeons shot in the Pacific Islands (Hemsley, Chall. Bot., L, 46). 

 Whether birds or currents first carried the fruits to Krakatau after 

 the eruption of 1883 is not known. It appears, however, that 

 the plant was first recognised there in 1897, and that in 1906 it was 

 well established amongst the strand vegetation (Ernst's New Flora 

 of Krakatau). 



It seems highly probable that this plant is a gift from the Old 

 to the New World through the agency of the currents. In this 

 respect the behaviour of the genus is closely similar to that of Scaevola 

 as described under the shore plants of that genus. Like Sccevola 

 the genus is predominantly Australian, eleven out of the sixteen 

 known species being peculiar to that region. Of the remainder, 

 three are peculiar to Africa, one is common to Ceylon and Borneo, 



