GEOGRAPHICAL DISTRIBUTION 489 



shows. The presence of three species of the typically Antarctic genus Camptoplites 

 (see p. 492) is in itself significant. 



Camptoplites bicornis var. quadriavicularis is also found at the Shag Rocks, near South 

 Georgia which has a predominantly Antarctic Polyzoan fauna (see below). The three 

 other varieties of C. bicornis are Antarctic, and the typical form came from an abyssal 

 station in the Antarctic region. 



C. asymmetricus is also found at South Georgia, and in the deeper water on the 

 Chilean coast (see below). Its nearest relative, C. areolatus, is Antarctic. 



Caberea darwinii var. guntheri is not known elsewhere, but resembles the Antarctic 

 form of C. darwinii, in contrast to the shallow-water Falkland specimens which repre- 

 sent the extreme sub-Antarctic type of the species (see p. 386). 



Cornucopina ovalis var. versa, on the other hand, shows definite affinities outside the 

 Antarctic, for, although the typical form is found at South Georgia, their nearest relative 

 appears to be the Victorian C. grandis. The variety is known from Kerguelen where it 

 was found in 36^ m. and may perhaps have been found in the Straits of Magellan 

 (see p. 403). 



Camptoplites atlanticus and Himantozonm obtusum, both of which extend into rather 

 more shallow Falkland waters, are not found elsewhere, but they, too, are related to 

 Antarctic species, Camptoplites latus and Himantozoum antarcticum respectively. 



Notoplites elongatus var. calveti comes next to these forms in order of depth and extends 

 into shallow water. The typical form is known from Kerguelen and Marion Island where 

 it forms part of a fauna with sub- Antarctic rather than Antarctic affinities (see p. 484). 



There is some evidence that the bottom water off the Patagonian Shelf may in part be 

 of Antarctic origin and character. A branch of the current of Antarctic surface water 

 from the Bellingshausen Sea is known to turn north towards the Falkland Islands and, 

 having sunk below the sub-Antarctic surface water at the Antarctic convergence, to 

 travel north, mixing with the lower layers of the Falkland current, which is a north- 

 ward current of sub-Antarctic surface water along the coast of Patagonia. (Information 

 obtained, about 1936, through Mr Clowes, from Dr Deacon's unpublished results. 

 Also see Deacon, 1937, pp. 32, 33, 51.) 



On the other hand, one of the species with Antarctic affinities {Camptoplites asym- 

 metricus) was also found on the Chilean coast where there is not such a strong northward 

 flow of Antarctic water. The specimen was obtained in 320 m. in one of the channels 

 between the islands and the mainland (Challenger St. 308). I am indebted to Dr Deacon 

 for information about the hydrological conditions in this region. 



Table 5 shows the species from South Georgia similarly tabulated in relation to 

 depth. It is less complete than Table 4, being based on little more than half the number 

 of stations, and, although there are very nearly as many stations from 190 m. downwards, 

 the 300-400 m. zone is untouched, so that a fair comparison can hardly be made. To 

 emphasize the Antarctic nature of the South Georgian fauna as a whole, Antarctic 

 species are marked A, and those whose nearest relative is Antarctic are marked A*. The 

 exclusively shallow- water fauna comprises a single species, Menipea patagonica, which is 

 chiefly found in the sub-Antarctic. 



