334 MOSTLY MAMMALS 
disappeared at an early date. All the other tortoise-islands 
in the Indian Ocean were inhabited. They include the 
Aldabra group, north-west of Madagascar, where the few 
tortoises now remaining in the south island are under 
Government protection, the Mascarenhas, or Mascarene 
group (Réunion, or Bourbon, Mauritius, and Rodriguez), 
the Amirantes, and the Seychelles. None of the Mascarene 
species survive in their proper home, and all were thought 
to be extinct, although a specimen has turned up from 
a distant island, to which it had been carried. Much the 
same may be said with regard to the Seychelle tortoises, 
which were exterminated long ago in their proper habitat. 
There seems, however, to be good reason for believing 
that a few survivors of the species have been preserved in 
islands to which they had been transported in ships. This 
transportation of tortoises from one island to another has 
indeed added considerably to the difficulty of unravelling 
the complicated history of the group, a specimen of the 
South Aldabra tortoise having been carried to one of the 
islands of the Chagos group, to the south of the Maldives, 
whence it was subsequently transported to Mauritius. 
The accounts left by the early voyagers show that in the 
Mascarene and other islands of the Indian Ocean, as well 
as in those of the Galapagos group, the tortoises formerly 
existed in enormous numbers. As regards the Galapagos 
islands, it is remarkable that there are no small-sized 
species; and the same holds good for the islands of the 
Indian Ocean, with the exception of Madagascar, where 
there is one comparatively small form (TZ. radiata). It 
should be added that, if we except Madagascar (where 
there is one moderate-sized carnivore), none of the tortoise- 
islands were ever the home of large and_ predatory 
mammals. This naturally suggests the idea that the 
