SEA-FLOOR DEPOSITS. PART I 329 



green grains (probably glauconite) are present, but the colour of the deposit is not entirely due to 

 these grains ; moreover the preserving liquid is coloured greenish yellow. Shelly material is present 

 in about the same proportion as the mineral constituent. It consists mainly of microscopic lamelli- 

 branch shells mostly in a fragmentary condition ; there is a variety of Foraminifera, which includes 

 Globigerina, Polystomella and other genera. The flocculent material contains an abundance of green 

 algal cells with mucilaginous walls ; these algae apparently contribute largely to the green colour of the 

 deposit. 



Station WS 84. 24. iii. 27. Lat. 52° 34' S. Long. 59 10' W (approximately). 7J miles S 90 W 

 of Sea Lion Island, East Falkland Island. 75 m. (Plate XVIII.) 



Coarse sand. A clean speckled sand with shells. The sand consists mostly of clear quartz grains 

 about 0-5 mm. in diameter; there are some dark green grains which may be glauconite. Much shelly 

 material is present ; mainly fragments of molluscan shells, it includes also small lamellibranchs (fry), 

 Foraminifera and echinid spines. 



Station WS 86. 3. iv. 27. Lat. 53 53' 30" S. Long. 60° 34' 30" W. 151 m. (Plate XVIII.) 

 Sand. A comparatively fine speckled sand with much shelly material, consisting of rounded or 

 subangular grains of clear quartz and other minerals, the average diameter being about 0-2 mm. 

 Occasional grains of hypersthene are noted. The shelly material includes fragments of lamelli- 

 branchs (many worn and rolled), echinid spines and Foraminifera. The small amount of muddy 

 material in the sample contains centric and compound diatoms, as well as flocculent aggregates. 



Station WS 87. 3. iv. 27. Lat. 54 07' 30" S. Long. 58 16' 80" W. 96 m. (Plate XVIII.) 

 Sand with shells and stones. A speckled sand with fragments of shale and large shells, especially 

 Pec ten. The sand itself is largely composed of shelly material, including remains of lamellibranchs, 

 Serpulae, Polyzoa, echinoids (spines), Foraminifera. Some detrital sand grains are present as well as 

 the shale fragments, some of which are highly glauconitic. Supernatant flocculent material contains 

 diatoms and possibly other small organisms. 



Station WS 88. 6. iv. 27. Lat. 54° 00' S. Long. 64 57' 30" W. 118 m. (Plate XVIII.) 

 Sand. A clean speckled sand, largely composed of rounded quartz grains less than 0-5 mm. in 

 diameter; rounded crystals of hypersthene up to 0-4 mm. in diameter are fairly common ; other dark 

 grains may be glauconite. The organic fraction includes much shelly detritus, rolled fragments of 

 echinoid spines, and Foraminifera, many of which are not waterworn. Polyzoa also occur, encrusting 

 small pebbles. 



Station WS 89. 7. iv. 27. Lat. 53 00' S. Long. 68° 06' W. 9 miles N 21 E of Arenas Point 

 Light, Terra del Fuego. 23 m. (Plate XVIII.) 



Gravel. A non-graded deposit. The largest constituents are rounded pebbles, up to 4 cm. in 

 diameter, encrusted with Polyzoa. There are smaller pebbles from 1 cm. diameter downwards, some 

 of quartz, others of coloured material. The sand grade contains a variety of heavy minerals. The 

 remaining constituent is a grey slimy mud composed of flocculent aggregates with sponge spicules 

 and tiny mineral grains. 



Station WS 90. 7. iv. 27. Lat. 52 18' S. Long. 68° 00' W. 13 miles N 83 E of Cape Virgins 

 Light, Argentine Republic. 82 m. (Plate XVIII.) 



Sand. The sample contains a large proportion of clean, rounded quartz grains, with an average 

 diameter of about 0-3 mm. ; grains of hypersthene are also fairly common. There is apparently no 

 shelly material. The finer fraction is composed of the usual flocculent material with small quartz 

 grains, diatoms and spicules. 



Station WS 91. 8. iv. 27. Lat. 52 53' 45" S. Long. 64 37' 30" W. 191 m. (Plate XVIII.) 

 Sand. A clean sand with a variety of mineral grains, up to about 0-5 mm. in diameter, rounded and 

 subangular in shape. Quartz and hypersthene are the most conspicuous minerals. Shelly material 



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