DISTINCTIVE CHARACTERS OF ORGANIZED BODIES. 19 
being the instrument of some special action or function, which 
it performs under certain conditions ; and the concurrence of 
all these actions being necessary to "the maintenance of the 
structure in its normal or regular state. Hence there is a 
relation of mutual dependence among the parts of an Organized 
fabric, which is quite distinct from that of mere proximity ; 
and this relation is most intimate, not in the case of those 
beings which have the greatest multiplication of parts, but 
among those in which there is the greatest dissimilarity 
the actions of the several organs. Thus it has been 
just shown that among Plants and Zoophytes, a small fraction 
of an organism may live independently of the rest; the 
necessary condition being that it shall either itself contain 
all the organs essential to life, or shall be capable of pro- 
ducing them,—as when the Jleaf-bud develops rootlets for 
its nutrition. This “vegetative repetition,” and consequent — 
capacity of sustaining the loss of large portions of the fabric, 
still shows itself in animals much higher in the scale than 
Zoo phytes ; thus it is not uncommon to meet with Star-fish 
in which not only one or two, out of the five similar arms, 
_but even three or four, have been lost, without the destruction 
_of the animal's life ; and this is the more remarkable, as these 
“arms are not simply members for locomotion or prehension, 
but are really divisions of the body, containing prolongations 
of the stomach. In like manner, many of the Worm tribes, 
Shoes bodies show a longitudinal repetition of similar parts, 
ean lose a large number of their joints without sustaining any 
considerable damage. In the bodies of the higher animals, 
however, where there are few or no such repetitions (save 
in the two lateral halves of the body), and where there is, 
consequently, a greater diversity in character and function 
_ between the different organs, the mutual dependence of their 
actions upon one another is much more intimate, and the loss 
of a single part is much more likely to endanger the existence 
the whole. Such structures are said to be more highly 
wrganized than those of the lower classes; the principle of 
division of labour” being carried much “further in them, 
| much greater variety of objects _being attained, and a much 
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