on board HM.S. ' Challenger? 473 



idea of the nature and distribution of the deposits which are taking 

 place in the oceans and seas we have visited. It will also furnish some 

 data and serve as the basis for speculations on the mode of origin of — 

 The deep-sea clays ; 



The formation of the manganese nodules ; 



The presence of the remains of surface animals (consisting of siliceous 



and carbonate-of-lime organisms) in some deposits, and their 



absence in others, &c. 



By pelagic Foraminifera are meant species of Globigerina, Orbulina, 



Pulvinulina, and of one or two other genera which are still undescribed, 



but which have been found abundantly in the surface-waters of the 



Pacific and South Atlantic oceans. 



When the final Eeport is prepared, the genera or species of the 

 organisms whose remains occur in each sample will be given. So also 

 for the mineral particles, and the ratio of these to each other and to the 

 amorphous, clayey, and calcareous matter will be more accurately stated. 

 At the present moment such an undertaking is in no way possible. 

 Those things which are most abundant in the sample are generally 

 mentioned first. 



Atlantic Ocean. 



England to Gibraltar. 



30th December, 1872. Lat. 41° 37' N., long. 9° 42' W. 1125 fathoms. 

 A blue mud containing: — Amorphous blue clayey matter; many 

 fine mineral particles ; many pelagic Foraminifera and Coccoliths 

 and Coccospheres. 



Sounding 1. 13th January, 1873. Lat. 38° 10' N., long. 9° 14' W. 

 470 fathoms. A green mud containing : — Amorphous clayey matter ; 

 many sandy particles ; pelagic and other Foraminif era ; spicules of 

 sponges ; pieces of Oorallites. Light green-coloured glauconitic casts 

 of the Eoraminifera remained after treatment with acid. 



Sounding 3. 14th January, 1873. Lat. 38° 26' N"., long. 9° 38' W. 

 560 fathoms. A dark green mud containing : — Amorphous matter 

 and many dark green grains and other mineral particles ; pelagic 

 and other Poraminifera, JSfefttni-spines, &c. Beautiful glauconitic 

 casts of all the carbonate-of-lime organisms remained after treatment 

 with acid. 



Sounding 4. 14th January, 1873. Lat. 38° 22' N., long. 9° 44' W. 

 1290 fathoms. A blue miid containing : — Much amorphous matter ; 

 many black, green, and white mineral particles ; many pelagic Fora- 

 minif era and few shells of Mollusca ; a few casts of the Foramini- 

 fera in glauconite. 



Sounding 5. 14th January, 1873. Lat. 38° 14' N., long. 9° 49' "W. 

 1475 fathoms. A blue mud containing : — Amorphous matter ; many 

 fine and some coarse mineral particles of green, white, and black 



