132 THE VOYAGE OF H.M.S. CHALLENGED. 



lasted much longer, and consequently extended over a larger tract, but at the same time 

 we can sec from this that the deep-sea Actinias are by no means exceptionally rare. 



The relative abundance of the Actinias among the deep-sea fauna is shown by the 

 fact that several species and several specimens of the same species were not unfrequcntly 

 found at the same station. Station 235 furnished the largest number of individuals, viz., 

 twenty specimens of Polysiphonia tuberosa and two colonies of Epizoanthus parasiticus 

 were taken at a depth of 565 fathoms. Stations 237 and 300 were distinguished by the 

 diversity of the forms dredged ; at the former four specimens of Cereus spinosus, two of 

 Paractis tubulifera, one of Porponia robusta, and one of Liponema rmdtiporum were 

 taken at a depth of 1875 fathoms, at the latter one Corallimorphus profundus, one Par- 

 actis excavata and one Opjhiodiscus sulcatus were taken at 1375 fathoms. The following 

 stations yielded also good results : — Station 299 ; depth, 2160 fathoms ; one Opiliioddscus 

 annulatus and one Polyopis striata. Station 157 ; depth, 1950 fathoms ; one Cereus 

 spinosus and one Corallimorphus rigidus. Station 147 ; depth, 1600 fathoms ; one 

 Bunodes minuta and one Sicyonis C7nssa. 



The stations in shallow water are far behind as regards the results of the dredgings. 

 The only stations worthy of special mention are Station 143, depth 120 fathoms, which 

 contributed two Halcampa clavus and one Leiotealia nymphcea to the Challenger 

 material; and Station 313, depth 55 fathoms, which contributed three Antholoba 

 reticulata, four Dysactis crassicornis, and two Dysactis rhodora. 



As regards the relation in which the fauna of the different depths stand to one another, 

 it may already be safely asserted that the greater the depth, the more the fauna varies 

 from that of the coast. I will make only two divisions, and compare, on the one hand, 

 the Actiniae from 10-500 fathoms, and on the other, the Actinias from 500-2900 fathoms 

 with the known forms essentially belonging to the coast. The first region gives on the 

 whole thirteen species and twelve genera, of which five species and two genera (Scytophorus 

 and Steplianactis) are new. The remaining twenty-one species and seventeen genera 

 belong to the second region (two genera, Phellia and Steplianactis, are represented in 

 both divisions), of which not less than twenty species and eleven genera are new. The 

 depths of 500-3000 fathoms are therefore inhabited by entirely different Actiniae, as even 

 the only species which cannot be considered as new, Ep>izoanthus parasiticus, approached 

 the first region, as it was taken at a depth of 565 fathoms. 



The varying character of the deep-sea fauna leads us to the third question already 

 started, viz., has life in the great depths a visible influence on the organisation of the 

 Actinias % This influence can be distinctly recognised in many forms, and is shown by the 

 nature of the tentacles which have undergone retrograde formation, and are transformed 

 first into tubes, and afterwards into simple openings in the oral disk. In Paractis 

 tubidifera (depth 1875 fathoms) the tentacles have the same constitution as in the 

 majority of Actinias, except in one point, that the terminal opening, which is usually 



