74 THE DEPTH AND MARINE DEPOSITS OF THE PACIFIC OCEAN. 



Calcium carbonate: 68.18 per cent, pelagic Foraminifera, mostly 

 broken, with a few Echinoid spines. 



Residue : 31.82 per cent; there is too httle material to determine the per- 

 centages of minerals and siliceous organisms. 



Siliceous Organisms form a large part of the " fine washings," and are 

 represented by Diatoms, broken Radiolaria, and Sponge spicules. 



Minerals ; most of the mineral particles pass off with the " fine wash- 

 ings," and include silicates too small for identification, and manganese grains. 

 Fine Washings, brown, flocculent, clayey matter, colored by the oxides 

 of manganese and iron, with fragments of minerals and siliceous organisms. 



No. 60. Station 4544,* 21st February, 1905. 

 Lat. 10° 38' N.; long. 106° 47.6' W. ; depth, 1955 fathoms. 



RED CLAY : sticky chocolate-brown clay, containing not a trace of calcium 

 carbonate. A very small quantity of material available for examination. 



Calcium carbonate (0 per cent). 

 Residue (100 per cent) : — 



Siliceous Organisms (traices), a very few Sponge spicules. 

 Minerals (about 1 per cent) ; the only mineral of appreciable size is 

 manganese in the form of grains 0.10 mm. in mean diameter ; other minerals 

 belonging to silicates are present, but are very minute and pass off with 

 the " fine washings." 



Fine Washings (about 99 per cent), brown flocculent clay, containing a 

 few minute mineral particles and siliceous remains. 



Note. — This sample is peculiar for such a depth, suggesting that the cal- 

 cium carbonate has by some means been removed. 



Appended are brief descriptions of a few samples which do not apparently 

 represent the actual deposit at the bottom, followed by a few notes on the 

 unlabelled samples : — 



Washed Samples. 



Station 4611, 18th October, 1904. 

 Lat. 10° 33' N. ; long. 88° 30' W. ; depth, 1792 fathoms. 

 GLOBIGERINA OOZE: the deposit is not in its original state, and must have 

 been subjected to washing during the process of collection ; it is quite inco- 

 herent and granular, and essentially composed of Foraminifera, pelagic and 



