DISTRIBUTION OF MARINE LIFE. 407 
perpetually succeeded by new creations of equal beauty. Happy 
the man whose eye is open to their charms! Every ramble 
through the woods and fieids is-to him a banquet of pure and 
inexhaustibte delight. 
The causes which confine the life of animals and plants to 
circumscribed localities are in many cases easily to be traced. 
The warmth or coldness of the sea, resulting from currents, 
geographical position, and depth; tranquil or disturbed, pure or 
troubled waters; abundance or scarcity of food, solidity or softness 
of the ground, sufficiently explain why many species of marine 
animals appear in some places in considerable numbers, while in 
others they are totally wanting. A superficial view of their 
organisation often shows us at once the physical properties their 
habitat must necessarily possess. By looking at a fucus we 
immediately see whether it requires the protection of tranquil 
waters, or is able to bid defiance to the floods; whether it is 
made to anchor upon the rock, or to sink its roots into a more 
yielding soil. 
In many cases, however, the causes which regulate the distri- 
bution of the sea-animals are still enveloped in darkness, and we 
no more know why the tropical seas bring forth in some places 
numerous coral-reefs, and none at all in other to all appearance 
just as favourably situated localities, than we do why the tea- 
plant is confined to a small corner of Asia, or the Peruvian 
cinchonas to a narrow girdle on the Andes. 
Evidently, besides the influences known to us, there are 
many other hidden ones at work, whose conflicting powers draw 
round every living creature a mysterious circle, whose bounds it 
is unable to transgress. Their discovery belongs to the future, 
and certainly forms one of the most interesting subjects for the 
naturalist’s inquiries. 
The geographical distribution of the terrestrial plants and 
animals is undoubtedly much easier to be ascertained than that 
of the denizens of the ocean. The naturalist is able to climb 
the highest mountains beyond the extreme limit of vegetation, 
and far above their most towering peaks his eye, piercing the 
transparent atmosphere, sees the condor soar in solitary majesty ; 
he can wander through the deepest glens, or even, penetrating 
into the bowels of the earth, examine and collect the forms of 
the subterranean flora; but it has not been given him to peram- 
