294 THE GALAPAGOS TORTOISES. 



viduals at different ages, or in different sexes, are such that measurements 

 taken of specimens and reduced to percentages of the direct length parallel 

 those from the other localities to so great an extent that they are of no real 

 assistance in determining varieties or species. 



Testudo elephantopus Harlan has under various names been reported from 

 five of the islands: — Espanola (Hood), Pinzon (Duncan), North Isabela 

 (Albemarle), Fernandina (Narborough), and Pinta (Abingdon). As will be 

 seen by reference to the chart, Plate 1, this distribution might have been effected 

 entirely by the currents after the species had secured a location on Espanola 

 or it may in part have been brought about by the intervention of man. The 

 agency of the currents, from the directions indicated by the arrows on the chart, 

 is entitled to much favor. For it is sheer assumption that denies the possibility 

 of drift and establishment by its agency on either of these localities to an animal 

 of such buoyancy, as also that denying ability to swim or otherwise exert itself 

 in the water to a creature possessed of so much muscular ability, endurance, 

 and persistence in walking and climbing. While the buccaneers, the whalers, 

 and the explorers have had something to do with distributing the tortoises since 

 the discovery of the islands by the whites there is a possibility that earlier 

 introductions perhaps including the earliest of all were due to aboriginal navi- 

 gators of the times of the Incas or farther back. Considering the possible 

 means of distribution, the amount of differentiation from such a species as T. 

 tabulata, Plate 2, the rapidity of growth the variability of the individual it 

 appears unnecessary to go back to the Tertiary or perhaps more than a few- 

 generations for the first appearance of the tortoises in the Archipelago. 



Among five so-called species placed under T. elephantopus there may be 

 one or more entitled to varietal rank. All of them have been styled races, 

 whatever that may have meant, but the individual descriptions given do not 

 supply the details necessary for characterization. 



The original measurements in inches, of several so-called species are: - 



Straight Straight Curved Curved Sternal Sternal 



