44 THE DEPTH AND MARINE DEPOSITS OF THE PACIFIC OCEAN. 



Fine Washings (43.93 per cent), earthy-brown in color when in great 

 quantity, composed of amorphous clayey matter, together with numerous 

 Radiolaria and Diatoms, which were too light to remain with the heavier 

 portions. The mineral particles present are exceedingly small, but augite 

 can still be recognized. 



No. 5. Station 4641, 7th November, 1904. 

 Lat. 1° 34.4' S. ; long. 89° 30.2' W. ; depth, 633 fathoms. 

 GLOBIGERINA OOZE: gray, with very little coherence, has a distinct 

 greenish tinge, very homogeneous, no macroscopic elements present. 



Calcium carbonate : 75.00 per cent, well-preserved shells of Foramin- 

 ifera, belonging principally to the genera Globigerina and Pulvimilina ; young 

 individuals are specially abundant. Other organisms were not detected. 



Residue : 25.00 per cent : — 



Siliceous Organisms ( 1.5 per cent ), gray clayey casts of Foraminifera, 

 perfect in shape, predominate over the organisms proper; Sponge spicules 

 are abundant, and in a good state of preservation, and parts of the skeletons 

 of Hexactinellidse may be seen. Many Radiolaria and Diatoms are present, 

 together with a few glauconitic casts and arenaceous Foraminifera. 



Minerals (1 per cent), all angular excepting the few glauconitic grains 

 present ; their mean diameter is 0.15 mm. The most typical mineral in this 

 deposit is augite, which is represented by two varieties : the ordinary 

 light brown, and the violet ; magnetite is fairly abundant, and so is hematite. 

 A red shapeless mineral is frequently observed, but cannot be determined, 

 as it is doubtless in course of decomposition, being sometimes tran.slucid and 

 birefringent, sometimes quite opaque. Plagioclase is also met with, and also 

 many minute splinters of colorless volcanic glass. Common green horn- 

 blende is present in small amount. Of glauconite only a few rounded grains 

 could be detected. 



Fine Washings (22.5 per cent) ; in a gray-brown clayey ground-mass are 

 many minute fragments of Sponge spicules, Diatoms, and Radiolaria, accom- 

 panied by the above minerals, principally augite. A very flocculent green 

 matter, floating in water, gives its color to the deposit. 



No. 6. Station 4649, 10th November, 1904. 

 Lat. 5° 17' S.; long. 85° 19.5' W. ; depth, 2235 fathoms. 

 RED CLAY : dark gray, plastic, drying into hard coherent lumps of a 

 lighter shade of gray. 



