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,
128
THE *BIOLOGY OF
in. the main the same courses as in Higher Vertebrates—
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forwar(is ventrally,
dorsally above the abdominal
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cavity, With several ramications between. These ramica.
tions have arisen through the increasing size and importance
of the various organs.
For example, the venous blood With
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its stores of food collected from the intestine makes its way
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forward to the liver, Where some of its constituents are
removed by the cells of the latter, then assemblesagain into
,
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a
large vein and passes forward to the heart. _, Similarly,
the Venous blood from the caudal region frequently passes
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ows forward ‘ventrally to heart (au and @) theriée’td îvenÏtralŸaärtaË(üïaô)
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through the kidneys, but there are rmany variations in the
details, '_ ;
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