W. K. BROOKS ON THE GENUS SALPA. 171 



No description can convey an adequate conception of the boundless 

 luxuriance of a coral island, but nothing else affords such a vivid picture 

 of the capacity of the sea- floor for supporting life. 



The marine plants are not abundant on coral islands, and the 

 animals depend either directly or indirectly upon the pelagic food-supply, 

 so that in this respect their life is like that of animals in the deep sea far 

 from land. 



The abundant life is not restricted to the growing edge of the reef, 

 and the inner lagoons are often like crowded aquaria. At Nassau, my 

 party of eight persons found so much to study in a little reef in a lagoon, 

 close to our laboratory, that for four months and more we found new 

 things every day, and our explorations seldom carried us beyond this 

 little tract of bottom. Every inch of the surface was carpeted with 

 living animals, while others were darting about among the corals and 

 gorgonias in all directions ; but this was not all, for the solid coral was 

 honeycombed everywhere by tubes and burrows; and, when broken to 

 pieces with a hammer, each mass of coral gave us specimens of nearly 

 every great group in the animal kingdom. Fishes, Crustacea, annelids, 

 molluscs, echinoderms, hydroids and sponges could be picked out of 

 every fragment, and the abundance of life inside the solid rock was 

 most wonderful. 



The absence of pelagic life in the landlocked waters of coral islands 

 is as impressive and noteworthy as the luxuriance of life upon and near 

 the bottom. 



On my first visit to the Bahama Islands I was sadly disappointed by 

 the absence of pelagic animals where all the conditions seemed to be 

 peculiarly favorable. 



The deep ocean is so near that, as one cruises through the inner 

 sounds past the openings between the islets which form the outer 

 barrier, the deep-blue water of mid-ocean is seen to meet the white sand 

 of the beach, and soundings show that the outer edge is a precipice as 

 high as the side of Chimborazo and much steeper. Nowhere else in the 

 world is the pure water of the deep sea found nearer land or more free 

 from sediment, and on the days when the weather was favorable for 

 towing outside, we found siphonophores and pteropods and pelagic mol- 

 luscs, Crustacea, salpae, and all sorts of pelagic Iarva3 in great abundance 

 in the open sea just outside the inlets. 



Inside the barrier the water was always calm, and day after day it 

 was as smooth as the surface of an inland lake. When I first entered 



