152 PLANTS, SEEDS, AND CURRENTS 



Cassia fistula, L., and Cassia grandis, L. 



The pods of these two trees, which are often two feet long in the 

 entire state, are characteristic of the foreign drift on the beaches of 

 the Turks Islands, though in a fragmentary condition. I found 

 them on the beaches of all the larger cays, such as Grand Turk, 

 Cotton Cay, Salt Cay, and Greater Sand Cay. Portions of the same 

 two fruits also came under my notice amongst the beach-drift of 

 Trinidad and Tobago. The association of the pods of these two 

 trees in the beach-drift of the West Indian region in localities so far 

 removed from each other is worthy of remark. Those of Cassia 

 fistula were also recorded by Morris from the stranded drift in 

 Jamaica (Chall. Bot., IV., 301). We must therefore regard these 

 singular fruits as regular constituents of West Indian beach-drift. 

 Their occurrence in this connection on the Turks Islands is specially 

 interesting, since the trees do not grow in those islands, and the pods 

 could only have been brought by the currents from the large islands 

 to the southward and eastward. On these beaches the pods of 

 Cassia grandis are more frequent than those of C. fistula. 



Since Nature associates these two trees in the drift, we will deal 

 with them together. Cassia grandis is indigenous in tropical 

 America and in the larger West Indian islands (Grisebach). It is 

 one of the several species of the genus that represent the remains of 

 the original Antillean flora of the great Caribbean land-mass now in 

 large part beneath the sea (Harshberger, Phytogr. N. Amer., p. 307). 

 But Cassia fistula is usually regarded as introduced to America from 

 its home in the Old World, although the matter is still one for dis- 

 cussion. However, from the facts given by Sloane, to be subse- 

 quently noticed, there seems little room for doubt that with Cassia 

 fistula in the West Indies we are concerned with an introduced tree. 

 De Candolle held with Sloane that it was brought by the Spaniards 

 to America (Geogr. Bot., p. 772) ; and both Bentham and Grisebach 

 regarded it as naturalised in the tropics of the New World. A good 

 deal of interest attaches itself to this point, since the pods of Cassia 

 fistula are amongst those found on the coasts of Europe with other 

 West Indian drift. 



But before proceeding further in this discussion I will refer to the 

 condition of the fruits of these two trees as presented on the Turks 

 Islands beaches. The seeds, it should be remarked, have no buoyancy, 

 being transported in the compartments of the buoyant pod ; but the 

 long fruits break up in time in the floating drift, and though sea-water 

 then penetrates some of the compartments, the fragments still float, 

 being kept up by the air confined in the other chambers and by the 

 buoyancy of the tissues forming the fruit. It is in this fragmentary 

 state that these pods usually occur in the Turks Islands beach-drift, 

 and also in that of other West Indian islands, the portions varying 

 from four to ten inches in length and being as a rule much " weathered. " 

 The smooth pods of Cassia fistula are, however, much better fitted 

 for ocean transport than those of C. grandis, which have a rougher 

 exterior and possess two lateral ribs that are very apt to be torn 

 away in the drift, thus exposing the seed-chambers along more or 



