NARRATIVE OF THE CRUISE. 51 



in which the polyps are directly sessile upon the stem, instead of being borne on lateral 

 pinnules, as they are in the more complex forms. One of the most important conclu- 

 sions to which Professor v. Kolliker has been led by the study of the Challenger collection, 

 is that the simpler forms of Pennatulida more especially abound in great depths. 

 There are altogether eight families in this lower group, of which seven are — with 

 the exception of one or two species — invariably found in deep water. Of these 

 the Umbellulidae and Protoptilidse are the most important, and have furnished the 

 greatest number of new species, many of which have also a wide horizontal distribu- 

 tion. The eighth family, that of the Veretillidse, seems, however, to be confined to 

 shallow water. On the other hand, the members of the higher group, comprising the 

 families Pteroeididaa, Pennatulida?, Virgularidse, and Renillidse are nearly always found 

 in depths less than 100 fathoms. 



With regard to horizontal distribution, the general conclusion arrived at is : — Of the 

 various families the Umbellulidse are the most widely distributed; they occur in the North 

 Polar Sea, in the Atlantic Ocean, in the South Polar Sea, in the Southern Ocean west of 

 Kerguelen Island, and in the North and South Pacific. The Stachyptilidse, Protocaulidse, 

 and Protoptilidse have two centres, one in the Pacific Ocean on the coasts of New 

 Zealand, New Guinea, and Japan, and the other in the North Atlantic and North Sea. In 

 the Pacific, Atlantic, and Southern Oceans, far removed from land, the representatives of 

 this order are exceedingly rare, but are more abundant as land and shallower water 

 are approached. The Anthoptilidae are only found on the east coast of America, but 

 range from Halifax as far southward as Buenos Ayres and Tristan da Cunha. The 

 Kophobelemnonidse and Veretillidse, on the other hand, appear to have a limited distri- 

 bution, but very little has been added by the investigations of the Challenger to our 

 knowledge of the distribution of these two families. 



Among the more complex forms, the Virgularidse and Pennatulidse are the most 

 widely distributed ; the latter are found on the coasts of Europe, China, Japan, Australia, 

 New Guinea, on the west coast of North America, and on the east coast of Africa. 

 The Pteroeididse have a well-defined centre in the southeast coasts of Asia, extending as far 

 northward as Japan, and as far westward as the Red Sea and the west coast of Africa ; 

 one species indeed, Pteroeides griseum, inhabits the Mediterranean. There are altogether 

 seven new genera and twenty-seven new species in the Challenger collection, and Professor 

 v. Kolliker has, in consequence, found it necessary to form a new systematic arrangement 

 of the suborder. 



Madeira. 



On the 2nd February the Madeira group was sighted, and the ship proceeded towards 

 the south end of the Dezertas to obtain soundings for the Lisbon-Madeira submarine cable 



