2 o DISCOVERY REPORTS 



which is not the same as Zimmer's Longithorax capensis from the southern hemisphere. I have sug- 

 gested the name of Longithorax nouveli sp.n. for this species from the northern hemisphere. 



Many species in the Discovery collection are to be found in the tropical and temperate waters of 

 both southern and northern hemispheres. A few, such as Gnathophansia gigas, G. zoea, G. ingens, 

 Eucopia unguiculata, E. grimaldi, E. australis and Boreomysis rostrata appear to have a very wide 

 distribution in all the oceans of the world, except the Arctic and Antarctic from which some of them 

 have not yet been recorded. It is interesting to note that, at any rate as far as the Discovery collection 

 is concerned, the species with the widest range are almost invariably very deep water forms and belong 

 to the more primitive groups of the Mysidacea. 



One of the most remarkable captures of the whole collection is that of four specimens of Antarcto- 

 mysis maxima at station 274, just south of the equator off St Paul de Loanda, Angola. This species has 

 always been regarded as a purely Antarctic form. Its capture at many stations around the coasts of 

 South Georgia and the Falkland Islands has extended its known geographical range considerably to 

 the northward, but its occurrence in tropical waters off the west coast of Africa is most surprising. 

 One other capture is worthy of especial comment, that of a species of My sis taken off the coast of South 

 Georgia. This is the first time that any species of this genus has been recorded from the southern 

 hemisphere. 



In order to show how far the Discovery collection has extended our knowledge of the distribution 

 of mysids in the southern seas, I have drawn up a list of new records and, for purposes of comparison, 

 I give also lists of those species which are known so far from the Atlantic Ocean only, from the 

 Antarctic and Southern Seas only and from the Atlantic and Indian Oceans only. Full details of 

 localities and the vertical distribution of species are given in the List of Stations and a note on the 

 distribution is given at the end of the record of each species. 



NEW RECORDS IN THE DISCOVERY COLLECTION AND OTHER 

 EXTENSIONS OF KNOWN RANGE 



(Locality given in brackets) 



Chalaraspidum alatum. New to South Atlantic (west of Cape Town). 



Gnathophausia ingens. New to western South Atlantic (off La Plata); new to southern temperate waters (Prince 



Edward Is. and off South Africa). 

 Gnathophausia gigas. Range extended considerably to southward in South Pacific (Bellingshausen Sea). 

 Gnathophausia zoea. New to central South Atlantic (west of Tristan da Cunha). 

 Gnathophausia gracilis. New to southern hemisphere (off St Helena). 

 Lophogaster schmidti. New to Indian Ocean (Arabian Sea, off Ras Hafun). 



Lophogaster challenged. Range extended considerably northward in eastern South Atlantic (off Cape Lopez). 

 Eucopia sculpticauda. Range extended southward in Indian Ocean (off East London and Durban). 

 Boreomysis rostrata. First record from surface waters; range considerably extended southward in Indian Ocean (off 



Heard Island). 

 Boreomysis sibogae (doubtfully). New to South Atlantic (west of Cape Town and off South Georgia). 

 Boreomysis atlantica. New to southern hemisphere (off Cape Town and off South Georgia). 

 Boreomysis inermis. Range extended considerably northward in South Atlantic (South Georgia). 

 Rhopalophthalmus egregius. Range extended northward in eastern South Atlantic (off Cape Lopez) and westward 



(off South Georgia). 

 Gastrosaccus sanctus. New to southern hemisphere (off west coast of South Africa and off South Georgia). 

 Anchialina truncata. Range extended considerably northward in eastern South Atlantic (off Cape Lopez). 

 Anchialina typica. New to eastern South Atlantic (Benguela Current). 



Gibberythrops acanthura. Range extended considerably southward in western Indian Ocean (off Durban). 

 Meterythrops picta. New to Indian Ocean (south of Madagascar). 





