ORNITHOLOGY OF THE ISLAND OF TOBAGO. 
a species discovered upon the continent since Darwin wrote of 
the zoology of these islands, and most interestingly brought for- 
ward their remarkable peculiarities. The Great Tortoise is known 
in many other parts of the world ; but the question has been in- 
geniously raised, Are not these islands the distributing point from 
whence they have been carried to India, the Mauritius, &c.? In- 
stead of the simple circumstance, that they may have been equally 
easily carried there, and from the solitude, unmolestedness, and 
abundant food of succulent cacti, have grown in size and increased 
in numbers, to the extent that the later navigators have found them, 
an extent which will soon decrease if the present destruction is 
carried on. The other reptile so much insisted upon as proving this 
point, and certainly elsewhere yet unknown, is a very remarkable 
one, but so far from proving its insulation, it possesses properties 
of transport enjoyed by few. 
It is an aquatic animal, going out to sea in pursuit or search for 
food, is an excellent swimmer, and apparently so formed by internal 
structure, as to be able to continue under water for a lengthened 
period, as a seaman performed the experiment and sunk one, with 
a heavy weight, in expectation of drowning it, but at the expiration 
of an hour the lizard was alive and quite active — and where then is 
the difficulty of such an animal passing (one would almost say in 
numbers) a distance of 500 or 600 miles \ The same solitude, and 
rest, and abundance of food, will account for their increase and 
size, and making these bleak shores as jj; were their own adopted 
territory. 
The ornithological distribution in the archipelago of islands now 
more immediately under consideration, is somewhat regulated by 
the same general laws ; some of the islands possess peculiar species, 
but in others, separated no great distance, one species seems to be 
supplied or represented by another quite distinct, and we cannot 
at once account for the discrepancy where the facility of intercourse 
with the continents and each island is so nearly equal. The aquatic 
birds and waders seem to range around all the coasts in neailj 
equal proportions, and from the facility with which they shift fiom 
place to place, there is no great variation within the range occupies 
by the archipelago; and it is from the incessorial and land bn s, 
that we must draw our conclusions of the ornithological distiibu 
lion. 
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