2 28 ANIMALS OF LAND AND SEA 



individualized by the greenish, golden, or silvery light which 

 betrays their presence and defines their outlines, while it illu- 

 minates the sea itself. Sometimes, but not often, on tempes- 

 tuous nights the phosphorescence, intensified by the motion 

 of the water, adds singularly to the wildness of the scene. Each 

 wave rises Hke a mass of molten iron and seems to threaten 

 the vessel with destruction; it breaks, then passes off in her 

 trail, and adds new beauty to her brilliant wake. In this 

 general illumination Mr. Agassiz observed that it is easy to 

 distinguish the different forms of life. The huge ctenophores 

 float by hke luminous balls among the myriad lesser lights 

 caused by the smaller jelly-fish, while the Portuguese men-of- 

 war resemble fire-balloons on the surface and spread the phos- 

 phorescence in all directions. 



As described by Moseley, when a large fish or a porpoise or 

 a penguin dashes through water full of little luminous creatures 

 their bodies are briUiantly Ht up, and their tracks are marked 

 by a trail of light. 



An excellent sketch of the conditions on the bottom in the 

 depths of the Norwegian Sea has been pubHshed by Professor 

 G. O. Sars. As he describes it, forests of those peculiar sponges 

 known as Cladorhiza, with tree-like branches, here deck the 

 bottom for long stretches. Among the branches of these Cla- 

 dorhizas are beautiful sea-scorpions or basket-stars, variegated 

 "fire-stars," and various crustaceans, while slow moving sea- 

 spiders or pycnogonids creep about these branches and with 

 their long proboscis suck out their organic juices. And among 

 the dead sponges a whole world of more dehcate plant-like ani- 

 mals flourish. In the open spaces between the sponge forests 

 beautiful purple star-fish creep about, and long armed brittle- 

 stars, together with numberless jointed worms of various kinds, 

 and round about different sorts of crustaceans swarm. Above 

 all else project, like high mast timber in a coppice, the um- 

 bellularians, some eight feet high, with their dehcate straight 

 stems and elegantly curved crowns formed of a group of polyps. 

 The' light of day does not penetrate to these great depths, but 



