COPEPODA. 3 



Monstrilla grandis (49°), Oithona siinilis (52°), Paramlaaus jMrcux (52°), Rhlncalanus 

 nasutus (52°), R. gigax (G5° 42'), Scolecithrix minor (4G° 46'). 



This list contains a striking number of forms which are usually associated with 

 more temperate regions, and, as Dr. Giesbrecht remarks, the failure in agreement with 

 the pelagic species of the ' Belgica ' is very striking, for only two species are common 

 to all collections. Comparing it with the results of the ' Discovery ' the same 

 extraordinary differences are manifest, only four species ( C. propinquus, C. simillimus, 

 Clausocalaims arcuicorni.'^, O'lthoim sijnilis) being common to both collections. 



In the ' Gauss ' collections, in the area between Kerguelen and the Winter Station, 

 appear a great number of species in excess of those either of the ' Belgica ' or 

 ' Discovery.' Whereas in the ' Belgica ' collection occur thirty species, of which nine- 

 teen only arc pelagic, in the ' Discovery ' collection are twenty-four species of pelagic 

 Copepoda ; but in the ' Gauss ' collection this number is more than doubled, and a 

 numljer of species occur even in the collections made round about the Winter Station 

 which are not entirely Antarctic, but extend a long way northwards through the 

 deeper waters of the Atlantic Ocean, and have been brought there probably by southern 

 currents. The species determined, however, show but little agreement with the list 

 enumerated above. 



The very extensive number of species captured by the ' Gauss ' naturalists is 

 probably due to the fact that the tow-nets were used at much greater depths than in the 

 case of either the ' Belgica ' or ' Discovery.' In the former, 500 metres appears to have 

 been the limit, whereas in the latter the collections may be considered to be practically 

 surface collections. If the tow-net had been used at the depths it was employed on 

 the ' Gauss,' viz., to 3,000 metres, the agreement between the respective captures 

 might certainly have lieen greater, and the number of species taken greatly 

 increased. 



In the ' Gauss ' collections appear only six species which agree with any of 

 the species referred to above (viz., Aetideus armatus, Calanus projnnquus and C. 

 tibniUlmus, Claufioadaiius arcuicornis, Oithona similis, Lucicutia flavicornis), and when 

 it is remembered that in the ' Belgica ' collection there are only two species, and in the 

 ' Discovery ' only four species, of the twenty-seven species enumerated by Giesbrecht 

 which are in agreement, the conclusion is inevitable either that the captures made by 

 the expeditions mentioned were unusual, or that the identification of species has in some 

 instances been erroneous. That unusual species do appear in these areas, even close to 

 the ice, is shown by the occurrence in the ' Gauss ' Antarctic collections of Corycceuv 

 ,spi'cio'<U'<, Sapphirina metallina, Aetideuf< armafiis, Lnbidocera acutifrons, Undeuclui'ta 

 major, Arietell us setosus, and others; and in the 'Discovery' collection in Lat. 56° 

 31' S., Long. 156° 19' 30' occurred Eucalanus siibtenuis, and in Lat. 49° 40' S., and 

 Long. 172° 18' 30" W., Pleuromainnia gracilis, several young Candace, Euchoeta 

 )n.arina, and Centropages violaceus, which belong undoubtedly to a subtropical or 

 warm temperate area, and arc to l)c regarded as accidental. 



VOL. IV. K 



