THE GALAPAGOS TORTOISES. 263 



names and the prospect is that they will ultimately prevail. The Archipelago 

 was surveyed by Colnett, 1793. The chart, Plate 1, with the positions of the 

 islands, directions of the currents, and the two series of names is sketched from 

 that published under the direction of the Secretary of the Navy by the United 

 States Hydrographic Office, 1915. From the directions of the currents it will 

 be seen that affinities with South American organisms would be of the most 

 natural imaginable, if dependence for origins 'of the flora and the fauna were 

 placed upon the marine drift. The Spanish names of the islands with their 

 English equivalents are as follows : — 



San Cristobal (Chatham).. 



Espanola (Hood). 



Santa Maria (Floreana) (Charles). 



Santa Fe (Barrington). 



Santa Cruz (Chaves) (Indefatigable) (Porter's). 



Tortuga (Brattle). 



Pinzon (Duncan). 



Isabela (Albemarle). 



Fernandina (Narborough). 



Rabida (Jervis). 



San Salvador (James). 



Marchena (Bindloe). 



Pinta (Abingdon). 



In what ever way the balance of the fauna reached the islands, immediate 

 concern here is with the tortoises, and there is a possibility that they may have 

 been introduced by men. No one would care to assert that they developed from 

 birds or even from marine chelonians. There appears to be a sort of general 

 agreement that they reached the Archipelago as tortoises not very different from 

 what they now are. There is no evidence as yet, in the way of fossils, that they 

 estabhshed themselves in the Tertiary or other formations earlier than the most 

 recent. Their affinities are so close to living species on the mainland there is 

 hardly room for doubt their ancestors were the same if- indeed a species of the 

 continent was not the direct progenitor brought, possibly, in the times of the 

 Incas or still earher by the aborigines. Because of the heavy and sohd structure, 

 one would not risk the suggestion that the Jaboty had drifted across the sea; 

 but there is greater likelihood that island forms may have been drifted from one 

 island to another after finding lodgment in the Archipelago. Whether it was 



