The sponge, whether considered as a single or compound animal, has the power to reproduce itself, and here the mystery of life is as much hidden as it is in God's highest creation. It has been stated that every sponge contains a large number of separate cells which carry on the operation of circulation and respiration, and may be likened to the heart and lungs of an animal of a higher creation. Zoologists claim that each one of these cells represents a separate animal, living in a common structure.

Familiar Talks on Science, Volume 1, 1899, p. 172 - Nature's Miracles (1900)