THE DEPTH AND MARINE DEPOSITS OF THE PACIFIC OCEAN. 57 



Residue : 46.99 per cent, dark chocolate-brown : — 



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

 a few arenaceous Foraminifera. 



Minerals (1.4 per cent), angular; mean diameter 0.1 mm., principally 

 augite ; magnetite is abundant, mostly as particles firmly attached to other 

 minerals ; felspars belonging to basic plagioclases are present, but cannot 

 be specifically determined ; also brownish and greenish products of decom- 

 position of some minerals, augite amongst others, as one particle of augite 

 is seen to pass laterally into a greenish-brown amorphous substance ; a 

 few flakes of hematite. 



Fine Washings (45.59 per cent), very flocculent, brown clay, with a 

 few mineral particles and siliceous remains. 



No. 27. Station 4695, 23rd December, 1904. 

 Lat. 25° 22.4' S. ; long. 107° 45' W. ; depth, 2020 fathoms. 



GLOBTGERINA OOZE: chestnut-brown, plastic and sticky; dries into 

 light reddish-gray coherent lumps. 



Calcium carbonate : 62.30 per cent, pelagic Foraminifera, mostly broken 

 shells and rather small individuals ; Fishes' teeth and Echinoid spines. 

 Residue : 37.70 per cent, rich chestnut-brown : — 



Siliceous Organisms (traces), a few Sponge spicules and arenaceous 

 Foraminifera. 



Minerals (0.5 per cent), angular; mean diameter 0.1 mm., with frag- 

 ments of palagonite 1 mm. in diameter, and a reddish decomposed fragment 

 of rock, 3 mm. in diameter. Augite, plagioclase (labradorite), magnetite, 

 and manganese grains are equally abundant. Of the minerals forming the 

 fragment of rock alluded to, only a few crystals of augite and plagioclase 

 have escaped decomposition, the remaining portion being transformed into 

 an amorphous reddish-brown substance. The trawl also brought up frag- 

 ments of pumice, volcanic glass, and palagonitic tuff, described elsewhere. 



Fine Washings (37.20 per cent), dark chestnut-brown flocculent clay, 

 very free from admixtures of mineral particles, though a few of these can 

 be seen. 



No. 28. Station 4697, 24th December, 1904. 

 Lat. 23° 24.4' S. ; long. 106° 2.2' W. ; depth, 2188 fathoms. 



RED CLAY : very dark chocolate-brown, with yellowish patches ; dries into 

 hard lumps, giving a shining brown streak. 



