But, paradoxical as it may seem, this
is nevertheless true, not only for this Class, but for many others in
the Animal Kingdom. The same numerical proportions, the same richness
and vividness of conception were manifested in the early creation as
now; and though many of the groups were wanting that are most prominent
in modern geological periods, those that existed were expressed in such
endless variety that the Animal Kingdom seems to have been as full
then as it is to-day. The Class of the Echinoderms is one of the most
remarkable instances of this. In the Silurian period, the Crinoids
stood alone; there were neither Ophiurans, Asteroids, Echinoids, nor
Holothurians; and yet in one single locality, Lockport, in the State
of New York, over an area of not more than a few square miles, where
the Silurian deposits have been carefully examined, there have been
found more different Species of Echinoderms than are living now along
our whole Atlantic coast from Maine to Florida.
There is nothing more striking in these early populations of the earth
than the richness of the types. It would seem as if, before the world
was prepared for the manifold existences that find their home here now,
when organic life was limited by the absence of many of the present
physical conditions, the whole wealth of the Creative Thought lavished
itself upon the forms already introduced upon the globe.
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