TORTOISES OF THE GALAPAGOS 
bouring continent of Africa range the elephant and the 
rhinoceros. The Indian elephant and the Indian 
species of rhinoceros do not flourish in the smaller 
islands of the Eastern Archipelago. With the tor- 
toises it is otherwise. The Mascarene islands and the 
Galapagos Archipelago are the spots haunted by the 
biggest existing tortoises, of -which the species 
T. daudim, from the south island of Aldabra, has fur- 
nished us with the largest living tortoise ; that speci- 
men was until recently alive at the Zoo. The puzzle 
as to how they got upon these islands is like that of the 
flies in amber or the apples in the dumpling. We can 
only infer, and inference has been of two kinds. It 
has been held that the Mascarene islands and the 
Galapagos are the last vestiges of submerged conti- 
nents, from which other inhabitants have dwindled 
away in correspondence with the shrinking of terra 
firma ; only the tortoises remained, and finding the 
locality congenial and competition scarce, they waxed 
fat and grew in bulk. Viewed in this way the presence 
of these giants is a clue to formerly existing continents. 
On the other hand, it is not so certain that they may 
not have reached the islands, when they were islands, 
by sea transit. Heavy though the colossal tortoises 
of the Galapagos are, they will breast the waves of the 
pond in their enclosure with some success, and float 
in quite a feathery fashion upon its bosom. If one 
tortoise, heavy with eggs, were safely piloted across 
the waves, a colony would be formed, and this event 
repeated once a century would account for all the facts. 
The success when once arrived at is not difficult of 
understanding ; it is the mode of arrival which puzzles 
us. The great Testudo daudimi, once at the Zoo, and 
to which reference has been made, measured fifty-five 
inches along the shell. To this has to be added some- 
thing for length of neck, and some of these big tor- 
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