CONCLUDING OBSERVATIONS. 359 
groups, as classes or sub-kingdoms, or smaller ones, as 
families or genera. It is in the typical forms that we 
have these plans fully brought to view; while there is in 
the aberrant, in proportion to the degree in which they 
are so, a departure from these plans, or, rather, a modi- 
fication of them, to suit the particular wants and habits 
in each case. Thus, in the Vertebrates, the plan of the 
skeleton is very perfectly developed in the higher ani- 
mals, and especially in man. But the general features of 
the plan are the same in all this sub-kingdom. This may 
be seen if we take the skeleton as a whole, as illustrated 
in the first chapter, or if we look at some particular por- 
tion of it, as the arm and hand, as illustrated in regard 
to the flipper of a Whale (§ 185), the anterior extremity 
of the Dugong (§ 195), the wing of the Bat (§ 58), and 
the wing of birds (§ 198). In the Articulata, the ring- 
like arrangement, seen so decidedly in most of the ani- 
mals of this sub-kingdom, as the Centipede (§ 381), is not 
really given up in those where it seems to be, as in the 
Crab tribe; but a careful observation shows that it is 
only modified by making some of the rings exceedingly 
broad, while others are made exceedingly narrow (§ 526). 
There is not here an abandonment of the general plan, 
but a departure or aberration from it to some extent, 
making an aberrant form, in distinction from the typical 
forms where the ring-like arrangement is fully carried 
out. What I have thus said of the Vertebrates and the 
Articulates is essentially true of all parts of the animal 
kingdom. 
625. The great wonder is that so much uniformity of 
plan can be made consistent with such extreme variety, 
the minutiz of exact adaptation being in all cases fully 
carried out. There would have been a much smaller dis- 
play of wisdom and skill, if the same variety had been at- 
tained without the extended general plans which we see 
were adopted. None but omnipotent power could so 
connect endless variations in minutie with so few typical 
forms and arrangements. 
