THE DEPTH AND MARINE DEPOSITS OF THE PACIFIC OCEAN. fi3 



Residue : 45.46 per cent, olive brown, slightly greenish : — 



Siliceous Organisms (0.25 per cent approximately), spherical Radiolaria, 

 Sponge spicules, and Diatoms. 



Minerals (traces), only manganese grains were recognized in the small 

 amount available for examination. 



Mne Washings (45.21 per cent), greenish olive-brown in color when in 

 a sufficiently thick layer ; under the microscope light-gray clay, with many 

 remains of siliceous organisms and a few mineral particles too small for iden- 

 tification, except manganese grains. 



No. 37. Station 4715, 2nd January, 1905. 

 Lat. 2° 40.4' S.; long. 90° 19.3' W.; depth, 1743 fathoms. 



GLOBIGERINA OOZE : light gray, nearly white, plastic when wet, chalky 

 when dry ; very little material. 



Calcium carbonate : 50 per cent, mostly pelagic Foraminifera, gen- 

 erally broken ; a few bottom-living forms (Rotalidfe), one or two Echinoid 

 spines. 



Residue : 50 per cent : — 



Siliceous Organisms (traces), Radiolaria, Diatoms, and Sponge spicules 

 equally abundant; also one or two arenaceous Foraminifera. 



Minerals (traces), one or two manganese grains, and probably a few 

 fragments of augite, having a mean diameter of 0.01 to 0.02 mm. 



Mne Washings (about 50 per cent), light-brown, flocculent clay, with 

 many fragments of siliceous organisms; a few extremely minute mineral 

 particles. 



No. 38. Station 4520,* 11th January, 1905. 

 Lat. 1° 46.8' S. ; long. 91° 36' W. ; depth, 1815 fathoms. 



GLOBIGERINA OOZE : the material consists of two layers : one light gray, 

 the other light brown, the brown one being more coherent when dried. 



Calcium carbonate (the percentage of calcium carbonate was deter- 

 mined in both the gray and the brown ooze, and curiously enough was found 

 to be absolutely the same in both cases, viz. : 45.50 per cent) : many species 

 of pelagic Foraminifera, mostly broken, with a good many Echinoid spines, 

 a few Fishes' teeth, and bottom-living Foraminifera (Rotalidae and Miliolidas). 



Residue : 54.50 per cent, rich brown : — 



Siliceous Organisms (0.10 per cent approximately), Radiolaria, Diatoms, 

 Sponge spicules, and arenaceous Foraminifera are equally abundant. 



