on board H.M.S. 'Challenger.' 493 



Sounding 184. 11th February, 1874. 1260 fathoms. Lat. 60° 52' S., 

 long. 80° 20' E. A diatomaceous ooze of pure white colour con- 

 taining : — Chiefly frustules of Diatoms and their broken-down 

 parts ; many Eadiolaria ; a few Globigerina ; a few white, black, 

 and red mineral particles (mica). 



Sounding 185. 14th February, 1874. 1675 fathoms. Lat. 65° 42' S., 

 long. 79° 48' E. A blue mud (greenish tinge) containing : — Much 

 amorphous clayey matter ; a great many white, black, and yellow 

 sandy particles (quartz &c.) ; some granitic pebbles ; a good many 

 frustules of Diatoms amongst the amorphous matter • a few Eadio- 

 laria ; two small Globigerina were noticed in the portion examined. 

 The mud did not effervesce with acid. 



Sounding 186. 19th February, 1874. 1800 fathoms. Lat. 64° 37' S., 

 loug. 85° 49' E. A blue mud containing : — Much amorphous clayey 

 matter ; some coarse and a very great number of very fine mineral 

 particles, as quartz, mica, and black and yellow particles ; a good 

 many frustules of Diatoms and a few Eadiolaria ; one or two small 

 Globigerina. 

 The above two soundings are in many respects like those we usually 



got when approaching a continent or large island, especially like those 



soundings off the coast of North America at 80 to 100 miles from the 



coast. 



Sounding 187. 23rd February, 1874. 1300 fathoms. Lat. 54° 18' S., 

 long. 94° 47' E. A yellowish-blue mud containing : — Much amor- 

 phous matter ; many coarse and fine mineral particles, quartz, mica, 

 and red and yellow particles ; many remains of Diatoms and 

 Eadiolaria; a good many pelagic Foraminifera (small Globigerina 

 only) ; might be called a Diatom-ooze. 



Sounding 188. 26th February, 1874. 1975 fathoms. Lat. 62° 36' S., 

 long. 95° 44' E. A diatomaceous ooze containing chiefly (of a 

 yellow colour) : — The frustules of Diatoms and their broken-down 

 parts ; many Eadiolaria ; no pelagic Foraminifera in the portion 

 examined ; a few quartz, mica, and other mineral particles ; a few 

 granitic pebbles came up in the trawl. 



Sounding 189. 3rd March, 1874. 1950 fathoms. Lat. 53° 55' 8., 

 long. 108° 35' E. A diatomaceous ooze of a straw-colour containing 

 chiefly : — The frustules of Diatoms and their broken-down parts ; 

 many Eadiolaria ; a few small Globigerina ; one or two quartz and 

 mica particles. 



Sounding 190. 7th March, 1874. 1800 fathoms. Lat. 50° 1' S., long. 

 123° 4' E. A white Globigerina- ooze containing : — -Very many 

 pelagic Foraminifera (Globigerina, Pulvinulinas, and a few Orbu- 

 linas) ; Coccoliths ; a good many Diatoms and Eadiolaria; one or 

 two quartz particles and one or two pieces of a cherty-like mineral. 



