528 Taylor. Endemism in the Bahama Flora. 



72 per cent, of Bahama endemics (the last four items in the tabulation) are 

 at the present time so distributed that they are found in essentially the 

 same form in several places that have never been connected, and often 

 separated by tremendous depths of the ocean. This fact is still further 

 emphasized by the 35-6 per cent, of the total endemics which are confined 

 to the group of isolated islands. Thus nearly three-quarters of the endemics 

 show, by their dispersal over these islands, that (a) they may be relicts, 

 which is somewhat confuted by the small number of endemics found all 

 over the archipelago, less than 10 per cent. ; (b) parallel evolution might 

 account for them, although there is no evidence for or against such a theory, 

 except possibly the great general similarity of habitat on practically all 

 the islands ; or (c) certain of these islands may always have supported these 

 and other species, and from which they spread and may still be spreading. 



As to the method of dispersal, the West Indian hurricanes have, as 

 the record for the last forty years indicates, passed through the Bahamas 

 in a generally north-westerly direction, but except for local effects such as 

 the case of the ' Hurricane Grass ', Fimbristylis spathacea, their action is 

 assumed rather than proven. Studies in the field as to frequency of 

 occurrence on different islands, on windward and leeward sides of the same 

 island, upon the air-buoyancy of fruits and seeds, their times of ripening 

 and falling as contrasted with the hurricane season, and some other matters, 

 are necessary in order to make, definite statements about the response of 

 the Bahama flora to these violent storms. They are so tremendous in 

 their ability to suck up small objects into the vortex, and move with such 

 regularity about 12 to 14 miles an hour, and in such definite paths, that it 

 would be surprising if they have not left their mark upon plant distribution. 

 What that may have been demands further field study. 



The Gulf Stream washes all the western side of the archipelago, but, 

 without field studies of the ability of the seeds to both float and retain 

 germinating power, such as the coco-nut is known to do, we can only 

 conjecture about the influence of this great current. This applies not only 

 to seeds that float directly, but to those that may become fastened to logs 

 or debris and thus be carried from island to island. 



Birds unquestionably carry seeds throughout the archipelago, but 

 we as yet know very little definitely about the amount of this, nor do any 

 of these three agencies of dispersal explain certain features of the distribution 

 of the endemics. Over one-third of all the endemics are confined to the 

 islands to the southward. With the Gulf Stream and hurricanes both 

 moving past these islands in a north-westerly direction and yet failing to 

 carry to a single island or key of the Great Bahama or Little Bahama 

 Banks one of these southerly endemics, it is clear that the distribution of 

 Bahama plants cannot be ascribed too readily to these agencies. Fifteen 

 per cent, of all endemics, however, are found both on the Great Bahama 



