INTRODUCTION. 15

described :—“ The possession of a nervous system being
supposed to be indispensable to the power of motion, it
has been considered the distinguishing characteristic of the
animal kingdom ; but in one division (4crita, comprehend-
ing Polypes, Infusoria, Animalcules, Sponges, &c.) no traces
of nerves have hitherto been discovered. The best charac-
teristic of the animal kingdom is the possession of a mouth
or aperture, through which food is received, and a stomach
by which it is digested; and this would include all the
organized beings which have ever been considered by na-
turalists to belong to the animal kingdom, except the various
kinds of sponges.”

No apecies of the large and useful class Fishes (Pisces) is
mentioned in Scripture, though the references to fish and
fishing are by no means uncommon. In Exodus vii. it is
related, in speaking of the Nile, that “ the fish that was in
the river died ;” and there is great interest in this statement,
when it is known that fish formed a considerable part of the
subsistence of the Egyptians. They ate them either fresh,
salted, or dried in the sun. Diodorus says fish was a
great article of export, and that from the time of King
Merris many persons found occupation in salting the fish
caught in the lake made by that prince, and called by his