COPEPODA 167 



area and at times occurred in large numbers. The complete record of its occurrence in 

 this survey is given in Appendix II. It was very " patchy " in its distribution ; for example, 

 on the C line in March 1926, the average numbers, per 50 m. haul, with the N 70 V net 

 at the five stations 10 miles apart, were 9, 324, 5, o and 487 respectively. Its general 

 distribution is shown in Fig. 76; and its vertical distribution in Figs. 77, 78. It was 

 most abundant between 250 and 100 m. but was occasionally taken between 1000 and 

 750 m. It showed indications of a vertical migration over a considerable range in 

 depth; this is described on p. 237. 



Racovitzamis antarcticus, Giesbr. Of general distribution but never abundant, and 

 never occurring in the top 100 m. 



This species is widely distributed in the Antarctic, being taken by the 'Belgica', 1 

 'Gauss', 2 'Scotia', 3 'Terra Nova' 4 and 'Aurora'. 5 



Centropagidae 



Pleuromamma abdominalis (Lubbock). A single male specimen was taken in the cold 

 surface layer at St. 36, 90-0 m. It was taken by the ' Terra Nova ', 4 but not south of 6o°. 



Pleuromamma xiphias, Giesbr. Four female specimens were taken at St. 36, 50-0 m., in 

 the cold surface layer. It has not been taken before in the Antarctic Zone. 



Pleuromamma robusta (F. Dahl). 



This species was of very general distribution but never abundant. It was taken at all 

 depths from 1000 m. to the surface. A complete record of its occurrence is given in 

 Appendix II. It was taken by the ' Terra Nova ' 4 but not south of latitude 53 S. 



Pleuromamma gracilis (Claus). 



St. 139 36 at 100-50 m. 



Like P. robusta it was taken by the ' Terra Nova ' 4 but not south of 53 S. 

 1 Giesbrecht (1902). 2 Wolfenden (1911). 3 Scott (1912). 4 Farran (1929). 5 Brady (1918). 



