on board H.M.S. 'Challenger. 3 513 



many internal and external casts of the Eoraminifera in a red sub- 

 stance, as on 15th August, 1874. 

 Two or three hardened pieces of the bottom, coated with manganese, 

 were in the trawl. 



Sounding 302. 6th October, 1875. 2385 fathoms. Lat. 22° 21' 8., 



long. 150° 17' W. No bottom came up in the sounding-tube. The 



trawl brought up some dark chocolate clay and many manganese 



nodules and sharks' teeth. "Washing away the amorphous matter 



from some of the bottom there remained a large amount of sediment, 



consisting almost entirely of small rounded red mineral particles. 



Many of these had the form of both Foraminifera and Eadiolaria ; 



and it seemed as if some substance had been deposited in and on 



these organisms. There were also many manganese particles ; one or 



two pelagic Foraroinifera. 



In the washing of the mud in the trawl were great numbers of sharks' 



teeth, the largest being 4 inches across the base. One piece of manganese 



concretion measured 18 x 12 x 2 inches, and had a mass of soft red or 



yellow clay in the centre. There were two or three pieces of pumice. 



Sounding 303. 7th October, 1875. 2450 fathoms. Lat. 23° 35' S., long. 

 150° 3' W. A dark brown clay, same as described yesterday, con- 

 taining : — Amorphous clayey matter ; rounded yellow minerals, many 

 Eadiolarian-shaped ; pieces of pumice and other minerals ; very many 

 manganese particles ; a few Eadiolaria. 



Sounding 304. 9th October, 1875. 2075 fathoms. Lat. 26° 9' S., 

 long. 145° 17' W. In the upper part of the tube a Globigerina- ooze 

 of a light brown colour containing : — Very many pelagic and other 

 Foraminifera ; Coccoliths, Ehabdoliths, and EcJiini-symes ; small 

 yellow crystals and pieces of a red and yellow cherty-like mineral ; 

 some amorphous clayey matter. In the lower part of the tube a 

 dark chocolate clay containing : — Much amorphous clayey matter ; 

 very many yellow crystals and pellets of peroxide of manganese ; a 

 few broken pelagic Poraminifera. 

 The transition from the one to the other deposit was quite gradual. 



This sounding was very like that on 16th September last. 



Eemains of Eadiolaria and other siliceous organisms appeared to be 



entirely wanting in this sounding. 



Sounding 305. 11th October, 1875. 1985 fathoms. Lat. 28° 22' S., 

 long. 141° 22' W. A Globigerina-oom of light yellow colour con- 

 taining : — Grreat numbers of pelagic Poraminifera ; Coccoliths and 

 Ehabdoliths ; EcMni-s-p'mes ; a good many Eadiolarian remains ; 

 amorphous clayey matter and manganese grains ; a few pieces of 

 vesicular lava, of a green colour, like that at the Hawaiian Islands. 



Sounding 306. 14th October, 1875. 2375 fathoms. Lat. 32° 36' S., 



2r 2 



