Snapping Turtles dwell in fresh-water streams, lakes and ponds. There 
are four species of these fresh-water turtles in North and Central America 
and one species found only in New Guinea. Their relatively large heads, 
long, alligator-like tails, rough shells, and above all their use of powerful, 
notched jaws, have given all of these turtles a well-deserved reputation for 
viciousness. 
The Musk and Mud Turtles are also found in North, Central and 
northern South America, except for the giant-headed turtle, native to bodies 
of fresh water in Siam, Burma and China. The American species number 
more than fifteen. Disturbed in their muddy haunts, these reptiles give off 
a musky stench by secreting substances from small skin glands. Many 
species are able to withdraw head and limbs into the shell, the under part 
of which is provided with front- and rear-hinged lobes. 
The twenty-four generic types of Water Turtles are distributed all over 
the earth with the exception of the Australian region. Their physical char¬ 
acteristics as a group encompass every degree of evolutionary adaptation 
from aquatic to terrestrial life. One of these, the Balagur turtle has a shell 
almost two feet long. Found in Bengal, Burma and Malaya, it is enabled 
by its webbed toes to lead a completely aquatic existence. The better-known 
painted turtles, sliders, diamond-back terrapins, as well as the pond and 
box turtles, will be treated more extensively later in the chapter. 
Land Tortoises bring to mind the gigantic long-lived inhabitants of 
the Galapagos Islands and a few remote archipelagos of the Indian Ocean. 
Closely related are more than seventy-five smaller species found throughout 
the tropical world. Perhaps the most curious land tortoise is the East African 
soft-shelled tortoise whose flexible shell permits it to hide in the crevices 
of its rocky homeland. 
Sea Turtles range throughout the principal seas and oceans. The giant 
trunk-back, about which very little was known until recently, attains a weight 
of more than fifteen hundred pounds and is the largest of all living reptiles. 
Until a few years ago no one had ever observed this turtle depositing its 
eggs, although adult specimens had been captured from time to time in 
various parts of the ocean. In general the sea turtles have the same habits. 
Snake-necked Turtles are able to withdraw their long necks and heads 
into the shell in time of danger. This group is known from examples found 
in South America, Australia and New Guinea. All its members are quite 
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