INTRODUCTION 



N 70 70 cm. tow-net. Mouth circular, 70 cm. diameter (27-5 in.): mesh graded, at cod-end 



74 to the linear inch. 

 N 100 I m. tow-net. Mouth circular, i m. diameter (3-3 ft.): mesh graded, at cod-end of 



stramin with 10-12 meshes to the linear inch. 

 N 450 4I m. tow-net. Mouth circular, 4! m. diameter (14-8 ft.): mesh graded, cod-end of 7 mm. 



(0-28 in.) netting lined for part of its length with 4 mm. (o-i6 in.) netting. 

 OTL Large otter trawl. Head rope 40 ft. long (12-2 m.): mesh at cod-end ij in. (3-2 cm.). 



RM Mussel rake. 



Sh. Coll. Shore collecting. 

 STN Sounding rod. Nansen-Ekman type. 



TYF Young-fish trawl. A bag of stramin, with 10-12 meshes to the linear inch, attached to 



a circular frame 2 m. diameter (6-6 ft.). 

 TYF 70 B Young fish trawl. With 3 or 4 ft. of No. 70 silk sewn round inside immediately above 



the bucket. 

 V Vertical. 



To the symbols for tow-nets (N 450, N 100, N 70, N 50, TYF and TYF 70) B, H or V 

 is always added to indicate whether the haul was made obliquely, horizontally or 

 vertically. For determining the depths of horizontal and oblique nets, Kelvin tubes or 

 depth gauges were employed. Their use is indicated by symbols in the 'Remarks' 

 column, and where no such symbol appears it is to be understood that the depth was 

 estimated. When the depth of termination of an oblique haul is written '( — o)' it must 

 be understood that the net failed to close at some intended intermediate depth and fished 

 all the way to the surface. The last part of the haul from the intended depth of closing 

 to the surface would usually occupy a small fraction of the total time of fishing. Further 

 details of the methods of fishing large nets are given by Marr (1938). 



For symbols used to denote meteorological observations, see Station List, 1931-33 

 {Discovery Reports, vol. xxi, p. 3). 



Soundings taken by the echo-sounding apparatus are marked with an asterisk. 



At the end of the lists (p. 196) will be found a summary of the stations made by the 

 R.R.S. 'Discovery IT from October 1935 to May 1937, with references to the charts 

 on which the station positions are marked. 



REFERENCES 



Atkins, W. R. G., 1923. The silica content of some natural waters and of culture media. Journ. Mar. Biol. 



Ass. U.K., xin, pp. 151-9. 

 Cooper, L. H. N., 1933. Chetnical constituents of biological importance in the English Channel, November 



1930 to January 1932. Part I. Phosphate, silicate, nitrate, nitrite, ammonia. Journ. Mar. Biol. Ass. 



U.K., xvin, pp. 677-728. Part II. Hydrogen-ion concentration, excess base, carbon dioxide and oxygen. 



Journ. Mar. Biol. Ass. U.K., xvin, pp. 729-54. Part III, June-December 1932. Phosphate, silicate, 



nitrite, hydrogen-ion concentration, icith a comparison with wind records. Journ. Mar. Biol. Ass. U.K., 



XIX, pp. 55-62. 

 1938. Salt error in determinations of phosphate in sea water. Journ. Mar. Biol. Ass. U.K., xxni, 



pp. 171-78. 

 Harvey, H. W., 1934. Measurement of phytoplankton population. Journ. Mar. Biol. Assoc., N.S., xix, 



pp. 761-73. 

 Marr, J. W. S., M.A., B.Sc, 1938. On the operation of large plankton nets. Discovery Reports, Vol. xviii, 



pp. 105-20. 

 McClendon, J. F., 1917. The standardization of a nno colorimetric method for the determination of the 



hydrogen-ion concentration, CO2 tension, and CO, and O, content of sea water, etc. Journ. Biol. Chem., 



XXX, pp. 265-88. 



