,v DEPTHS AND DEPOSITS OF THE OCEAN 149 



is then called Radiolarian ooze ; sponge spicules, though present 

 in nearly every bottom-sample examined by us from deep and 

 shallow water, very seldom take any considerable part in the 

 formation of the deposits. 



The calcareous remains of foraminifera, corals, alcyonaria, Calcareous 

 annelids, Crustacea, echinoderms, bryozoa, molluscs, tunicates, '■'^"^^'"^• 

 and fishes seem to bulk more largely in deep-sea deposits than 

 the siliceous remains. The Globigerina and Pteropod oozes and 



the Coral muds 



and sands owe 



their names to 



abundance in 



Fig. 116. 

 Clathrocaniuin regintv, Haeckel. From the surface (magnified). 



Cinclopyra m is infiindi- 



hulum, Haeckel. From 

 the surface (magnified). 



them of the re- 

 mains of pelagic 



foraminifera (see 

 Figs. 1 18 to 121), 

 of pelagic molluscs (Figs. 122 and 123), or of coral fragments, 

 while the valves of ostracods (Figs. 124 and 125), the spines 

 of echinoids, the spicules of alcyonaria and tunicates, and 

 the otoliths of fishes are among the most constant of the 

 calcareous remains occurring in the deposits, though rarely 

 found in any great abundance. Reference may also be made to 

 the teeth of sharks (see Figs. 126 and 127) and the earbones of 

 whales (see Figs. 128 and 129) found occasionally in all deposits, 

 but characteristically in the Red clay areas especially of the 



