Note 18 — Chapter IV · THE MORPHOLOGICAL COMPOSITION OF ANIMALS.
Reading edition
Though the subdivision into chambers of the shell does not correspond to the subdivision into cell-units it may still be held that since in the solitary types the subdivision of the nucleus is followed by formation of new individuals which separate, and since in the compound types the subdivision of the nucleus is followed by growth and formation of new chambers, the compound type must be regarded as an aggregate of the second order.