OF THE KERGUELEN REGION OF THE GREAT SOUTHERN OCEAN. 489 



degrees further to the north than the eight stations making up the Kerguelen group of 

 stations, and this may have a bearing on the different results in the two groups of stations. 

 The more productive hauls in the deep water of the Kerguelen Region may perhaps be 

 purely accidental, but a more likely explanation is to be found in the physical conditions 

 of the region towards the Antarctic, as suggested in the first paragraphs of this paper. 



Of the 272 species of Metazoa captured in the deep-water stations of the Kerguelen 

 Region, it is to be observed that not one species is common to all the eight stations nor 

 even to any seven of the stations ; one species occurred at six stations, one at five 

 stations, 2 species each at four stations, 1 3 species each at three stations, and 40 species 

 each at two stations. In the two deep-sea stations nearest to each other — separated by 

 a distance of 122 miles — there were only 22 species in common out of a total of 145 

 species of Metazoa. This does not seem to indicate any very wide distribution of deep- 

 sea species within the Kerguelen Region, not indeed much wider than in the case of the 

 shallow-water species as stated on pages 432-433. Again, of the 272 deep-sea species, 

 164 species are at present unknown outside of the Kerguelen Region, and only 48 out of 

 the 272 species occur in the twenty-nine deep-sea trawlings and dredgings in the other 

 regions of the Southern Hemisphere south of the tropics. The total number of species of 

 Metazoa taken by the Challenger in depths over 1000 fathoms south of the tropic of 

 Capricorn was 523. Of these, 336 species, or 64 per cent, of the total number present, 

 were taken neither in any of the Challenger's trawlings within the tropics nor to the north 

 of the tropics. We thus see that deep-sea species are not apparently much more widely 

 distributed than shallow- water ones, for, as has been stated on page 434, 61 per cent, 

 of the Kerguelen shallow-water species have not as yet been procured outside that area. 

 It may therefore be expected that further dredgings in the deep sea towards the Antarctic 

 will yield a large number of new species of marine organisms. 



The Challenger's trawlings and dredgings around Marion, Kerguelen, and Heard 

 Islands, in depths less than 150 fathoms, yielded in all 533 species. There were about 

 forty hauls with the trawl and dredge, but this large number of hauls yielded only 

 about double the number of genera and species procured in the eight deep-sea hauls 

 in depths greater than 1260 fathoms. In the trawlings between 50 and 150 fathoms 

 the hauls were very much more productive than in depths less than 50 fathoms. In 120 

 and 105 fathoms off Kerguelen the notebooks say never before were so many animals 

 procured in the trawl, and in 75 fathoms off Heard Island it is said that the bottom was 

 teeming with animal life. These two stations were situated just about the mud-line off 

 the eastern — that is to say the leeward — coasts of Kerguelen and Heard Islands. Off 

 the western or windward shores the mud-line must be situated at a much greater depth, 

 for a gravelly bottom was found at a depth of 150 fathoms between these islands. 



The total number of species collected by the Challenger at Kerguelen in depths less 



than 50 fathoms appears to be only 130 species ; in some cases the hauls were from less 



to deeper than 50 fathoms, so that the separation at this line is not very distinct, audit is 



' therefore not possible to state the number with great certainty. If now we add to these 



