INTRODUCTION 55 



BURDWOOD BANK 



This is a large shoal of from 80 to 150 m. in depth situated south of the Falklands and separated 

 from them by deep water, 500-2000 m. The shoal lies east of Tierra del Fuego, and it is now generally 

 accepted that the line of folding represented by the Andes and their former continuity in what is 

 now termed the Scotia Arc passed through the Burdwood Bank and not the Falkland Islands. A trough 

 of moderately deep water, 250-500 m. severs the bank from Tierra del Fuego, and the ridge connecting 

 it to the eastward with Shag Rocks and South Georgia varies between 1000 and 2000 m., severed in 

 several places by deeper water of between 3000 and 4000 m. (Herdman, 1932, pp. 205-36). 



From his studies on fossil Foraminifera dredged from the Burdwood Bank, Macfadyen (1933) states 

 on p. 16 in summarizing these fossil occurrences that the ' beds are clearly shown to be the continuation 

 of those exposed on Tierra del Fuego and Staten Island, and a part of the (renamed) Scotia Arc of 

 folding, which is continued on a trend precisely determined by soundings to lie on the line of the Shag 

 Rocks, South Georgia, Clerke Rocks, South Sandwich Islands, South Orkney Islands to the South 

 Shetlands and Graham Land'. 



Only a small molluscan list of fifty-five species is available for this area (Melvill & Standen, 191 2, and 

 the Discovery Committee's Collections), but at least thirteen species are apparently restricted to the 

 locality. Of the remainder, fifteen are found in the Falkland Islands, but only three of them, Davisia 

 cobbi, Broohila calypso and Colpospirella algida, are not generally distributed in the Magellanic Province. 

 The bulk of the fauna is Magellanic, but four Antarctic species, Schizotrochus euglyptus, Pellilitorina 

 pellita, Balcis antarctica and Paradmete fragillima, here apparently reach their northern limit for the 

 American Quadrant. 

 PELECYPODA Burdwood Bank Check List 



Hochstetteria sublaevis (Pelseneer, 1903); Melvill & Standen, 191 2. 



H. wandelensis (Lamy, 1906); Melvill & Standen, 191 2. 



'Crenella decussata Montagu 1808' Melvill & Standen, 19 12; probably not this European species. 



Cyamium denticulatum Smith, 1907; Melvill & Standen, 1912. 



Carditella pallida duodecimcostata Melvill & Standen, 1912 (T.). 



Venericardia congelascens Melvill & Standen, 1912 (T.). 



Astarte magellanica Smith, 1881; Melvill & Standen, 1912. 



'Diplodonta lamellata Smith, 1881'; Melvill & Standen, 1912. 



Davisia cobbi Cooper & Preston, 1910; Melvill & Standen, 1912. 



'Kellyia cycladiformis Deshayes, 1855'; Melvill & Standen, 191 2. 



'K. magellanica Smith, 1881'; Melvill & Standen, 1912. 



GASTROPODA 



Schizotrochus euglyptus (Pelseneer, 1903); Melvill & Standen, 1912. 



Scissurella eucharista Melvill & Standen, 1912 (T.). 



S. supraplicata Melvill & Standen, 1912 (T.). 



Parmaphorella melvilli (Thiele, 1912); Melvill & Standen, 1907 (T.). 



Puncturella conica (d'Orbigny, 1841); Melvill & Standen, 1912. 



Calliostoma modestulum Strebel, 1908; Melvill & Standen, 19 12. 



Brookula calypso (Melvill & Standen, 1912) (T.). 



Liotella coatsianum (Melvill & Standen, 1912) (T.). 



' Cyclostrema' gaudens Melvill & Standen, 191 2 (T.). 



Subonoba fuegoensis (Strebel, 1908); Melvill & Standen, 1912. 



S.paucilirata (Melvill & Standen, 1912) (T.). 



5. sulcata Strebel, 1908; Melvill & Standen, 1912. 



S. turqueti (Lamy, 1906); Melvill & Standen, 191 2. 



