LAND AND SEA ANIMALS 170 



fresh waters of our globe have one group of fishes, the lung- 

 fishes, Dipnoi, which do not occur in the ocean, and there are 

 no marine Amphibia. The air-breathing insects and si)iders 

 are, with very few exceptions, never marine. Tliere is one 

 truly sea-going insect, Halohates, a species of bug which lives 

 in the Sargasso Sea. Certain animals that have taken to land 

 have in time returned to their ancestral home. Amonsfst these 

 may be reckoned, on the sea shore, a few spiders, mites and 

 insects, the very poisonous sea-snakes, and probably the 

 dolphins. The great bulk of the Crustacea are marine and 

 fresh-water, but mainly marine. They, like so many other 

 large groups, have never taken to the air. When the authors 

 of the Anti- Jacobin so passionately exclaim ; 



Ah ! who has seen the mailed lobster rise, 



Clap her broad wings, and soaring claim the skies? 



the answer, in the language of those curious mammals, the 

 politicians, is "in the negative." 



Fig. 67. A Lung-fish, Ceratodus forsteri. After E. S. Goodrich. 



Great expanses of inland waters are salt and some contain 

 a number of marine genera ; thus the Caspian, though less salt 

 than the ocean, harbours the seal, the salmon and the herring. 

 But such lakes as the Dead Sea and the Great Salt Lake of 

 Utah have become so concentrated as to render almost all 

 life impossible. 



The saline Lakes grow salter by degrees 

 'Till pickled salmon swim the astounded seas. 



Origin of Life from the Sea 



One of the greatest adventures of the organic world must 

 have been when, as Solomon in his "Wisdom" tells us, 



The things that before swam in the water, now went upon the ground. 



12-3 



