pacifica_, has a whitish luminosity, and differs from the others materially in form and structure. In many of the ports of tropical and semi-tropical America, it is the custom to bathe in the ocean at night, the warmth of the water rendering such recreation enjoyable. A gentleman newly arrived at one of the places on the Pacific coast proceeded at night to take a bath, and, upon rising from the water, was astonished and amazed to find that his entire body was luminous, seeming covered with a coating of light, which he found originated from innumerable minute phosphorescent animals, which clung to his garments, and changed the water all about to a golden hue. A distinguished professor at Keil was, perhaps, the first to discover luminous microscopic animals.[2] The largest of these minute creatures is about one-eighth of a line, the smallest from a forty-eighth to a ninety-sixth of a line in size. Giglioli has made some interesting observations regarding the phosphorescence of the lowest class of animal life, the protozoans, and with his colleague, Professor de Fillipi, intends publishing the results of their observations.[3] CHAPTER II. THE METEORS OF THE SEA. As the rushing comets dim the brightest luminaries with their radiance, so the ocean meteors, the moving _medusæ_, seem to excel in the glory of their light. The sea-jellies are among the commonest forms of the seashore. In the summer months the silvery sands are strewn with their glassy disks; unattractive then, but, once launched and imbued with life, possessed of many beauties of form and color. They range in size from those almost invisible to the naked eye, to giants weighing, it is estimated, over a ton. Many have a complicated structure; yet, in nearly all, the solid parts of the animal rarely represents over five per cent of the whole; and in specimens of a familiar northern kind, _Aurelia_, 95.84 is water. Little opportunity for light in such a creature, one would say; yet the simple jellies are numbered among the chief illuminators of the upper region of the ocean. I have observed them in the Atlantic, the Pacific, and in the Gulf of Mexico, in waters of various degrees of temperature; but, perhaps, the finest exhibition of their phosphorescence was seen off Boon Island, on the coast of Maine. The ocean surface seemed fairly bespangled with these living gems, which appeared surrounded by a halo of light. Each tentacle seemed to glow with an intense white heat; and, at a short distance, the streamers resembled delicate lace, wrought in curious designs. Peering into the depths, they appeared everywhere, moving in all directions, surrounded by the mysterious light whose office it is difficult to conjecture. [Illustration: PLATE III. LUMINOUS SEA JELLY. (_Thaumantius._) PRUNING-KNIFE FISH. (_Zanclus._) LUMINOUS CORAL.]