NATURAL SELECTION, AND THE ANTIQUITY OF LIFE 221 



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 concep- 

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

 garden-like, and the beautiful fishes of black and golden yellow 

 and iridescent cobalt blue hover like birds among the thickets of 

 yellow and lilac gorgonias. 



The parrot fishes seem to be cropping the plants like rabbits, 

 but more careful examination shows that they are biting off the 

 tips of the gorgonias and branching madrepores or hunting for the 

 small Crustacea which hide in the thicket, and that all the apparent 

 plants are really animals. 



The delicate star-like flowers are the vermilion heads of boring 

 annelids or the scarlet tentacles of actinias, and the thicket is 

 made up of pale lavender bushes of branching madrepores, and 

 green and brown and yellow and olive masses of brain coral, of 

 alcyonarians of all shades of yellow and purple, lilac and red, and 

 of black and brown and red sponges. Even the lichens which 

 incrust the rocks are hydroid corals, and the whole sea-garden is 

 a dense jungle of animals, where plant life is represented only by 

 a few calcareous algae so strange in shape and texture that they 

 are much less plant-like than the true animals. 



The scarcity of plant life becomes still more notable when we 

 study the ocean as a whole. On land herbivorous animals are 

 always much more abundant and prolific than the carnivora, as 

 they must be to keep up the supply of food, but the animal life of 

 the ocean shows a most remarkable difference, for marine animals 

 are almost exclusively carnivorous. 



The birds of the ocean, the terns, gulls, petrels, divers, cormo- 

 rants, tropic birds and albatrosses, are very numerous indeed, and 

 the only parallel to the pigeon roosts and rookeries of the land is 

 found in the dense clouds of sea-birds around their breeding 

 grounds, but all these sea-birds are carnivorous, and even the birds 

 of the seashore subsist almost exclusively upon animals such as 

 mollusca, crustacea, and annelids. 



