4 R. NORRIS WOLFENDEN. 



While the number of species captured was in each case comparatively small, the 

 number of individuals in any one haul in the case of the ' Discovery ' was very great. 

 The rule w y hich appears to hold good for tow-netting in the north part of the North 

 Atlantic, viz., that the further north we go the smaller the number of species, but the 

 immensely increased preponderance of individuals of certain species, certainly holds 

 good as regards the South Polar regions. Immense numbers of the small copepod 

 Ctenocalanus vanus appear in some of the hauls, to the almost entire exclusion of 

 any other species, and in other cases the larger copepod Euchceta antarctica appears 

 in great preponderance. Calanus acutus and, to a lesser extent, Calanus propinquus 

 also preponderate largely. Similarly, Metridia gerlachei appears in most of the 

 captures. 



The collections of the ' Gauss ' provide information which is not given by those of 

 the ' Discovery ' or of the ' Belgica,' namely, that several species which appear 

 in the Southern Polar Sea also occur in the deeper water of the Atlantic Ocean 

 to the northwards of the Antarctic area. But as this properly belongs to the report 

 of the ' Gauss ' collections which I have in hand, I forbear its discussion in 

 this place. 



Two questions are suggested by Dr. Giesbrecht in his ' Belgica' report, viz., (l) 

 Does the Antarctic area possess a peculiar fauna ? (2) Is the small agreement of the 

 Antarctic copepod fauna with that of the nearest seas due to defective research, or is it 

 that the area of the pack-ice has its own peculiar fauna ? and the further questions as 

 to whether the admixture of Polar and Antarctic fauna occurs in the deep ocean, or 

 whether there are physical and bibgenetic conditions in the Polar regions which differ 

 from those in the warm seas and prevent such exchange of species, receive some 

 elucidation from the collections of the ' Gauss.' 



With regard to the first question, viz., Does the Antarctic area possess its own 

 peculiar fauna ? it must be remarked that from the results of the three collections 

 named the typical copepod fauna (pelagic) of this region consists in the following : 



Calanus acutus Oncca curvata, similis, frigida, notopus, 

 simillimus conifer a, 



propinquus Scolecithrix glacialis 



Rhincalanus grandis Oithona similis 

 Euchoeta antarctica ,, frigida 



austrina Gaetanus antarcticus 



similis Haloptilus ocellatus 



Ctenocalanus vanus Paralabidocera hodgsoni 



Heterorrhabdiis austrinus Stephus longipes 

 Eucldrella magna antarcticum 



Spinocalanus antarcticus Ectinosoma antarcticum 



Metridia gerlachei Microcalanus pusillus 



