[Illustration: PLATE XVII. PYROSOMA AND DIVER. (_See page 84._)] LIVING LIGHTS A POPULAR ACCOUNT OF PHOSPHORESCENT ANIMALS AND VEGETABLES BY CHARLES FREDERICK HOLDER FELLOW OF THE NEW-YORK ACADEMY OF SCIENCES, ETC.; AUTHOR OF “ELEMENTS OF ZOOLOGY,” “MARVELS OF ANIMAL LIFE,” “THE IVORY KING,” “WONDER WINGS,” ETC. LONDON SAMPSON LOW, MARSTON, SEARLE, AND RIVINGTON, St. Dunstan’s House FETTER LANE, FLEET STREET, E.C. 1887 [_All rights reserved_] TO MY FATHER, THIS VOLUME IS GRATEFULLY INSCRIBED, IN REMEMBRANCE OF DAYS PASSED AMONG THE LIVING LIGHTS OF THE OUTER REEF. PREFACE. The object of the present work is to interest young people in natural history by the presentation of an attractive--indeed, marvellous--phase of nature, and to encourage healthful outdoor observation, as well as habits of investigation. The subject chosen for this work--that embracing the phenomenon of luminosity in animals, plants, and inorganic matter, and especially those that seem intended as illuminators of the ocean--is one which has ever possessed a fascination for the author. During many years spent on Southern shores, in constant association with the most attractive features of marine life, the remembrance of the splendors of the night festivals of these wondrous ocean forms is most enduring. No fairy tale of human invention can relate to us more fascinating scenes than are realized in Nature’s carnivals of the sea. Not only is the surface of the ocean, when lashed into foam by the tempest, luminous, but the greater depths, where the water is cold, near the freezing-point, and subject to pressure so great that instruments of glass are shattered and reduced to powder, abound in living lights. And this abyssal region, covered by miles in depth of water, and which was formerly considered to be the most desolate region upon the globe, is inhabited by light-givers of marvellous beauty and brilliancy. The little _Malacosteus_, with its gleams of yellow and green; _Stomias_, with sparkling side-lights; the dazzling effulgence of _Pyrosoma_; the comet-like glare of _Medusæ_, with their tints of many colors,--present a series of wonders which must excite the admiration of the most indifferent observer.