ECONOMY OF THE BODY—«I
139
.
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One thing is very clear in the
The
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organs have not kept pace With the growth of the
,
organs and body. They have been unable to follow the
_
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previously acquired rhythmic of segmental plan, such
'
we
see
in the skel€ton,—'àd fori_,af'time;'fthe—Ëlÿiph has
reassumecl an Old function bn a large
_
,_
salts not Wanted by
and blood m‘oîœr1p1gicÿès 1nthe
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,
body,Where they Can “do leaSt'harm;'
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-
,
we
can ude'rstandthef origin of a Skeleton, internally» as
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"
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vertebral column añd skull,
,
as : plates, scales, andf
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The internal» Skeleton offshes—r'is clearly an adaptation
to movements ,in’sa“ mediüm completely surrounding the
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organisx,bütthe ‘èXternal'skelet0n was not necessary. It
,
wasa aœiélent of growth and many shes manage without
,
.
it;
Higher animals have nOt' escaped from similar accidents;
,
,
’The Teleosts have made a special use of the excretory,,
and have improved upon the heavy?
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‘
armour
earlier;Ganoids,
except from anïæstheätic
'_
..
_poi_nt of vieÏn‘r‘fit,is_”;_d0übtfuläWhether—
,
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,
' _ anyadvantageTheloss
the ..blood—ha‘s ,
pmbablyledtotbelatterhavmg
,
{ _ —_:
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energy SisÊ,-Çsed
the 1mperm€— i'
ability
'Ïf ;