Taylor. Endemism in the Bahama Flora. 



531 



Vernonia has five species in the Bahamas, four endemics among them. 

 No other Vernonia is known on Inagua but the widely distributed 

 V. bahamensis, which is also endemic in the archipelago, and from 

 which the endemic V. obcordata peculiar to Inagua must have been 

 derived. 

 In all these ten genera, except Agave and Nashia, it is difficult to 

 avoid the conclusion that endemics peculiar to Inagua have been derived 

 from other and much more widely distributed species also known to grow- 

 there. Agave, with all its species endemic, and only one of which besides 

 A. Nashii is also found on Inagua, is a peculiar case. In this genus 



The 



BAHAMA ISLANDS 



English Miles 



aWa' lings l 



a 



21 



' .CAICOS u J 

 '-ulANK 



T, 



urVs 



Note the dotted lines that mark the limits of the old land masses of the Bahamas, now represented 



by the Banks and the scattered islands. 



we are confronted with a wealth of scattered progeny but a dearth of 

 parents. The most widely distributed endemic is A. bahamana, but it 

 is unknown from Inagua, and is so far recorded only from the islands on 

 the Great Bahama Bank. In other words, we are faced with two endemic 

 century plants on Inagua, and with Nashia inaguensis, none of which have 

 any relatives now on the island from which they could have been derived. 



There is, of course, always the chance that the progenitors of these 

 endemic century plants and of Nashia have failed of survival, and that 

 these endemics and others in the archipelago represent the end-series of 

 a pre-existing flora, which the great specialization of habitat has produced. 

 The sterility of the soil, limited rainfall (salt is recovered by evaporation of 



