But this luminosity is not entirely confined to the minute creatures of the sea. Some fish have the power of emitting light. Some species of the shark emit a greenish light; and the sun-fish is said, when seen down in the sea on a dark night, to glow like a white-hot cannon-ball. Fish when dead and putrid frequently glow in the dark with a truly magnificent light, as can be proved by every one who will take the trouble to procure several kinds of fish, and keep them, for the purpose of proving the fact, in a dark closet.
Of all the minute inhabitants of the deep, that which is to our mind the most curious, both as to its nature and its stupendous works, is the coral insect. This creature is much too important to be dragged in at the tail of a chapter. We will, therefore, commence its history in a new one.