DB. A. GtfNTHEE ON GIGANTIC LAND-TOETOISES. 
253 
these latter among themselves. All these species appear to have become extinct in 
modern times. 
2. These extinct Tortoises of the Mascarenes are distinguished by a flat cranium, 
truncated beak, and a broad bridge between the obturator foramina. 
3. All the recent examples of gigantic Tortoises in our museums said to have been 
brought from the Mascarenes, and the single species which is known still to survive in 
a wild state in the small island of Aldabra, have a convex cranium, trenchant beak, and 
a narrow bridge between the obturator foramina, and are therefore specifically, if not 
generically, distinct from the extinct ones. 
4. On the other hand there exists the greatest affinity between the extinct Masca- 
rene Tortoises and those still inhabiting the Galapagos group. The latter must be 
considered to be indigenous to this archipelago. 
5. Among the Galapagos Tortoises five species can be distinguished at present ; they 
are inhabitants of different islands of the group. 
I propose to preface my detailed description of the various species by a general 
account of the historical evidence given by travellers who have met with those Tortoises, 
whilst the scientific part of the literature will be better referred to in the descriptions 
of the several species. 
Historical evidence. 
Nearly all the voyagers of the 16th and 17th centuries who have left accounts of 
their adventures and discoveries in the Indian and Pacific Oceans mention the occur- 
rence, in certain isolated islands or groups of islands, of gigantic Land-Tortoises in 
countless numbers. The islands on which they met with these animals, although all 
between the equator and southern tropic, form two most distant zoological stations, 
widely different in their physical characteristics. One of those stations was the 
Galapagos Islands, the other comprised Aldabra, Reunion, Mauritius, and Rodriguez. 
But they had this in common, that at the time of their discovery they were unin- 
habited by man or even some larger terrestrial mammal. Not one of those voyagers 
ever mentions having met with those Tortoises in any other island of the tropics or in 
any portion of the Indian continent ; and it is not likely that one or the other should 
not have mentioned the fact if he had seen them in some novel locality. In fact 
the hardy sailors of that period took the greatest interest in these animals, which 
were to them a most important article of food. At a time when a voyage now 
performed in a few weeks took as many months, when every vessel, for defence’ sake 
and from other causes, carried as many people as it was possible to pack into her, 
when provisions were rudely cured and but few in kind, those tortoises which could be 
captured in any number with the greatest ease within a few days proved to be a most 
welcome addition to the stock. The animals could be carried in the hold of the ship 
or in any other part, without food, for months, and were slaughtered as occasion 
required, each tortoise yielding, according to size, from 80 to 200 pounds of whole- 
31DCCCLXXV. 2 M 
