444 THE VOYAGE OF H.M.S. CHALLENGER. 



Of the numerous species of Hyalonema no one form was represented in two oceans. 

 In the Atlantic Hyalonema toxeres was found near St. Thomas, Hyalonema {Stylocalyx) 

 thomsoni west of the Azores, Hyalonema lusitanicum to the south-west of Portugal 

 and west of the Straits of Gibraltar, as also at an undefined locality in the middle of the 

 South Atlantic. The two s^jecies of Hyalonema found in the South Indian Ocean were 

 Hyalonema conus to the south-west of Australia, and Hyalonema (Stylocalyx) clavigerum 

 to the west of the Crozets Islands. 



Of the species of Pheronema the Challenger found Pheronema carpenteri in the 

 Atlantic to the north-east of Bahia, and Pheronema glohosum and Pheronema giganteum 

 in the Pacific, oft' Little Ki Island in the Malay Archipelago. Polioj)ogon amadou occurred 

 in the Atlantic, south-west of the Canary Islands, and PoUopogon gigas in the Pacific, 

 between the Eaoul and Kermadec Islands. Semperella schultzei finally was obtained 

 both at the well-known locality near the Philippine Island, Zebu, and also in the Malayan 

 Archipelago off" Little Ki Island. 



As to the Farreidfe, Farrea occa occurred both in the Atlantic off" the island of St. 

 Thomas, and also in the Pacific at the Philippine and off" the Kermadec Islands, while 

 Farrea clavigera was only found in the Pacific near the Bauda Islands. Undefined 

 species of this remarkable, and apparently widely distributed genus, were found in all 

 the three oceans at various localities. 



Five species of Eurete were found in the Pacific, four of them off Little Ki Island 

 and one at the Philippines, but in the Indian Ocean no Euretid was found, and in the 

 Atlantic only the single species Lefroyella decora off" the Bermudas. Aphroccdlistes 

 hocagei occurred at several localities in the Atlantic, Ap>hrocallistcs ramosus only in the 

 Pacific at the Philippines. Chonelasma was represented in all the three oceans, by Chone- 

 lasma lamella both in the South Indian Ocean (near the Crozets Islands) and in the Pacific 

 (off Kermadec), by Chonelasma hamatum only in the Pacific at the last named locality. 

 Some undefined frao-ments of Chonelasma occurred at different localities in the Atlantic. 



Of Tretodictyidaj the Challenger found in the Pacific Hexactinella lata, Cyrtatdon 

 solutus, Fieldingia lagettoidcs, and Sclerothamnus clausii, all near the Little Ki Island, 

 and in the South Indian Ocean an undefined Hexactinella fragment near the Crozets. 



The Mseandrospongidse found in the Atlantic were Dactylocalyx patella off the 

 Bermudas, and near the Spanish Coast, and Myliusia callocyathus off" the West India 

 Island of St. Thomas. The Pacific yielded Mylkisia callocyathus off Little Ki Island 

 and near the Bandas, and likewise Aidocystis zittelii. 



In regard to the proportionate richness of the two temperate and the tropical zones, 

 it is necessary first of all to note the absolute number of localities yielding HexactineUida 

 in these three regions. The number of species in each zone must then be noted as in 

 the following tables (VI., VII.), and these statistics collated with the total number of 

 dredgings and trawlings in the respective regions. 



