274 THE ORIGIN OF THE OLDEST FOSSILS, ETC. 



to the point where these various Hnes met each other in a common 

 source, although it forces us to beheve that the common source 

 once had an individual existence. Embryology teaches that each 

 Ime once had its own representative at the surface of the ocean, 

 and that the early stages in its evolution have passed away and 

 left no record in the rocks. 



If we try to call before the mind a picture of the land surface 

 of the earth we see a vast expanse of verdure, stretching from 

 high up in the mountains over hills, valleys, and plains, and through 

 forests and meadows down to the sea, with only an occasional lake 

 or broad river to break its uniformity. 



Our picture of the ocean is an empty waste, stretching on and 

 on, with no break in the monotony except now and then a flying 

 fish or a wandering sea-bird or a floating tuft of sargassum, and 

 we never think of the ocean as the home of vegetable life. It 

 contains plant-like animals in abundance, but these are true ani- 

 mals and not plants, although they are so like them in form and 

 colour. At Nassau, in the Bahama Islands, the visitor is taken in 

 a small boat, with windows of plate-glass set in the bottom, to visit 

 the " sea gardens " at the inner end of a channel through which 

 the pure water from the open sea flows between two coral islands 

 into the lagoon. Here the true reef-corals grow in quiet water, 

 where they may be visited and examined. 



When illuminated by the vertical sun of the tropics and by 

 the light which is reflected back from the white bottom, the pure 

 transparent water is as clear as air, and the smallest object forty or 

 fifty feet down is distinctly visible through the glass bottom of the 

 boat. As this glides over the great mushroom-shaped coral domes 

 which arch up from the depths, the dark grottoes betw-een them 

 and the caves under their overhanging tops are lighted up by the 

 sun, far down among the anthozoa or flow^er animals and the 

 zoophytes or animal plants, which are seen through the waving 

 thicket of brown and purple sea fans and sea feathers as they toss 

 before the swell from the open ocean. 



There are miles of these " sea gardens " in the lagoons of the 

 Bahamas, and it has been my good fortune to spend many months 

 studying their wonders, but no description can convey any con- 

 ception of their beauty and luxuriance. The general effect is very 



