on board H.M.S. 'Challenger. 3 499 



a good deal of amorphous clayey and calcareous matter; fine 

 mineral particles (pumice) ; a few siliceous spines. 

 The trawl contained several pieces of water-logged cocoanut wood and 

 some pieces of pumice. 



Soundings inside the Barrier reef gave : — A coral-mud, made up of much 

 amorphous calcareous matter, debris of coral, Foraminifera, &c. 



9th to 16th September, 1874. 10 to 70 fathoms. The soundings and 

 dredgings between Cape York and the Arm Islands, across the 

 Arafura Sea, were all shallow water, 10 to 70 fathoms. In each 

 case the bottom was a green mud containing : — Many sandy 

 particles, as quartz, mica, and rounded mineral particles of a green 

 and black colour ; much amorphous green- coloured clayey matter; 

 broken pieces of shell ; shore forms of Foraminifera, as Textularias, 

 Eotalias, &c, and Echini-sipmes &c. ; a few remains of Diatoms. 

 After treatment with acid there always remained internal casts of the 



Foraminifera. Pelagic Foraminifera, Coccoliths, Ehabcloliths, Pteropods, 



and Eadiolaria appeared to be nearly or quite absent in the bottom and 



in the surface-waters. 



Cape York to Hongkong. 



Sounding 219. 23rd September, 1874. 800 fathoms. Lat. 5° 41' S., 

 long. 134° 4' E. A green mud containing : — Much green amor- 

 phous clayey matter ; many small mineral particles of a white, black, 

 and green colour ; a few pelagic and other Foraminifera ; a few 

 Eadiolarians and Diatoms. 



Sounding 220. 24th September, 1874. 580 fathoms. Lat. 5° 2Q' S., 

 long. 133° 19' E. A green mud containing: — Green-coloured amor- 

 phous matter; very many pelagic Foraminifera, Pteropods, and 

 Coccoliths ; a great many small mineral particles ; one or two Ea- 

 diolaria and a few Diatoms. 

 Many pale-green casts of the Foraminifera remained after treatment 



with acid. A section of 2 feet 3 inches came up in the tube ; the lower 



layers were of a blue rather than a green colour, and contained fewer 



Foraminifera than the upper layers. 



26th September, 1874. 129 fathoms. A blue mud containing: — A 

 great many pelagic Foraminifera and some Pteropod shells. 

 These were imbedded in a fine amorphous mud of a blue colour. In 

 the dredge there came up some large pieces of rock, which required a 

 sharp blow with a hammer to break. They contained many Foramini- 

 fera, and appeared to be merely hardened portions of the bottom. 



Sounding 221. 28th September, 1874. 2800 fathoms. Banda Sea. 

 Lat. 5° 24' S., long. 130° 37' E. A blue mud with a red upper 

 layer, containing : — Amorphous cWey matter ; many fine and a few 



