Lester Ward speculates that life remained aquatic for the vast periods that paleontology would indicate; Cambrian, Silurian, Devonian, Carboniferous - a duration greater than all subsequent time - for the reason that the creature had not progressed beyond the stage when it could move otherwise than in a straight line when actuated by desire for food or mate.

I cannot pass over this beautiful aquatic without giving it a place amongst the ornamental plants with which our country abounds.