334 DISCOVERY REPORTS 



Station WS 392. 17. ii. 29. Lat. 62 52' S. Long. 59 26' W. 591 m. (Plate XX.) 



Dark sand. This small sample consists of sand, dark-coloured from the abundance of opaque 



grains of volcanic glass which reach 0-25 mm. in diameter. Grains of quartz occur but sparingly. 



Zeolitic aggregates are also noted. 



Station WS 393. 17-18. ii. 29. Lat. 62°4i'S. Long. 59 41' W. Three samples from depths of 

 900-1000, 1051 and 1 138 m. (Plate XX.) 



Diatomaceous mud. The three samples are very similar in character and are typical of diatom- 

 aceous mud. The usual flocculent material encloses angular sand grains (mostly below O'Ojmm. in 

 diameter) and a variety of diatoms. The genera Cosdnodiscus, Thalassiosira, Cocconeis, Fragilaria, 

 Corethron and Rhizosolenia are the most conspicuous forms. In detail the samples show noteworthy 

 differences. The largest mineral grains are noted in the sample from 1138 m., in which grains with a 

 diameter of 0-5 mm. are noted, while mineral fragments up to 0-2 mm. are common at the inter- 

 mediate depth. Nearly all the grains are sharply angular, and many of them are splinters of volcanic 

 glass. 



Station WS 394. 18. ii. 29. Lat. 62 51' S. Long. 6o° 40' W. 274 m. (Plate XX.) 

 Terrigenous mud. The bulk of this sample consists of mineral grains, mostly angular in shape, 

 and ranging downwards in size from a diameter of about 0-25 mm., the average being roughly 

 0-05 mm. Among the mineral material are grains of quartz and vesicular volcanic glass, and occa- 

 sional small grains of glaucophane. There is a considerable amount of fine, flocculent matter which 

 contains some frustules of Cosdnodiscus and Fragilaria. The diatoms are not plentiful, hence this 

 deposit is classed as terrigenous mud. 



Station WS 395. 19. ii. 29. Lat. 63 48' 30" S. Long. 62 26' W. 297 m. (Plate XX.) 

 Diatomaceous mud. This sample is a typical diatomaceous mud. The mineral grains are small, 

 mostly less than 0-05 mm. in diameter, though some are o-i mm. across. Green hornblende, hypers- 

 thene (0.1 mm.) and glaucophane (o-i mm.) are present, as well as fragments of volcanic glass. 

 Diatoms are present in some abundance, the largest being species of Cosdnodiscus and Triceratium 

 with a diameter of about 0-2 mm. The genera Thalassiosira, Cocconeis, Fragilaria, Corethron and 

 Rhizosolenia are also represented. A single example of a sphaeroid radiolarian is noted. 



Station WS 396. 19. ii. 29. Lat. 63 38' 30" S. Long. 62 28' 30" W. 318 m. (Plate XX.) 

 Diatomaceous mud. The coarser fraction contains angular mineral grains, some of them more 

 than 0-25 mm. in diameter, but the great majority are much smaller. Grains of quartz, green horn- 

 blende and glaucophane are fairly common in occurrence together with splinters of volcanic glass. 

 Diatom frustules are plentiful in the finer fraction, Cosdnodiscus, Thalassiosira, Asteromphalus, 

 Cocconeis and Fragilaria being the most abundant genera. Rotaline Foraminifera are occasionally 

 seen. The flocculent material is of the usual type. 



Station WS 397. 19. ii. 29. Lat. 63 29' 25" S. Long. 62 37' W. 150 m. (Plate XX.) 

 Sand. This sample is a small quantity of clean sand of which the grains are mainly between 0-25 

 and 0-05 mm. in diameter. Subangular to rounded in shape, the majority are quartz grains, but some 

 are opaque. Several grains of glaucophane are noted, but the sample is too small for any judgment to 

 be pronounced on its relative abundance in the deposit. 



Station WS 399. 20. ii. 29. Lat. 62 50' S. Long. 61° 58' 30" W. 738 m. (Plate XX.) 

 Sand. Two fractions are somewhat sharply differentiated in this small sample. The coarser con- 

 stituents are mineral grains varying between 0-5 and o-i mm. in diameter. Some angular grains are 

 fragments of brown volcanic glass, which is sometimes vesicular in character. There are also occa- 

 sional grains of glaucophane. The finer fraction consists largely of small angular fragments of quartz 

 mingled with flocculent material in which some diatoms are present. Cosdnodiscus, Biddulphia, 

 Fragilaria and Rhizosolenia are the genera noted. 



