40 THE DEPTH AND MARINE DEPOSITS OF THE PACIFIC OCEAN. 



elongate bone, and several smaller fragments ; also 9 lightly coated delphinoid 

 ear-bones. 



"Station 4711, depth 2240 fathoms. Two very slightly encrusted 

 Lamna teeth ; 2 delphinoid ear-bones, one being a large, very heavily en- 

 crusted tympanic, the other a moderately coated tympano-periotic ; also a 

 number of corroded fragments, all charged with manganese, and betraying 

 only obscure indications of organic origin. 



"Station 4721, depth 2084 fathoms. No fish remains; 4 delphinoid 

 tympani ; 3 specimens of Kogia, one having the tympanic and periotic fused, 

 all lightly coated with manganese. 



" Station 4732, depth 2012 fathoms. One splendidly preserved Carcharo- 

 don crown without manganese coating, but with several worm-tubes adhering 

 to it ; ... no cetacean bones. This and the next following station lie 

 within the barren area. 



" Station 4736, depth 2289 fathoms. One small Carcharodon, 6 Oxyrhina, 

 13 large-sized Lamna teeth, all stained dark brown and very thinly coated 

 with manganese ; 3 delphinoid tympani, and 1 much decayed cetacean tooth 

 corresponding in size to Hyperoodon, more or less chocolate-colored. 



" Station 4740, depth 2422 fathoms. One splendidly preserved Carchar- 

 odon tooth ; . . . 1 Kogia, and 2 delphinoid ear-bones." 



Detailed Descriptions of the Deposit-Samples. 



(Numbered consecutively as collected; the stations marked with an asterisk are Hydrographic Stations 

 where soundings alone were made.) 



No. 1. Station 4630, 3rd November, 1904. 

 Lat. 6° 53' N. ; long. 81° 42.5' W. ; depth, 556 fathoms. 



GREEN SAND : dark green arenaceous material, which, when dried, is 

 quite incoherent, thus showing the absence of clayey matter. The dried 

 deposit is somewhat lighter in hue than the wet one. 



Calcium carbonate : 5.23 per cent, essentially composed of Foraminifera, 

 mostly Globigerinidae, together with a few broken Echinoid spines. 



Residue : 94.77 per cent, same color and consistence as the deposit itself : — 

 Siliceous Organisms (1 per cent), represented by a few broken Sponge ' 

 spicules. 



Minerals (90 per cent) ; if this sample really represents the deposit on 

 the bottom of the sea, it is abnormally rich in minerals. As the minerals 

 are essentially represented by glauconite, this deposit would be even richer 



