462 THE JOURNAL OF GEOLOGY. 



boring annelids or the scarlet tentacles of actinias, and the 

 thicket is made up of pale lavender bushes of branching madre- 

 pores, 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 repre- 

 sented 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 stud)- 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 ani- 

 mals are almost exclusively carnivorous. 



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

 morants, 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 ani- 

 mals such as mollusca, Crustacea and annelids. 



The seals pursue and destroy fishes ; the sea-elephants and 

 walruses live upon molluscs ; the whales, dolphins and por- 

 poises and the marine reptiles all feed upon animals and most 

 of them are fierce beasts of prey. 



There are a few fishes which pasture in the fringe of seaweed 

 which grows on the shore of the ocean, and there are some 

 which browse among the floating tufts of algae upon its surface, 

 but most of them frequent these places in search of the small 

 animals which hide among the plants. 



In the Chesapeake Bay the sheepshead browses among the 

 algae upon the submerged rocks and piles like a marine sheep, 

 but its food is exclusively animal, and I have lain upon the edge 

 of a wharf watching it crunch the barnacles and young oysters 

 until the juices of their bodies streamed out of the angles of 



