peesident'(5 .u)Dbess. 105 



can secrete or the other destroy shell most rapidly. In this 

 battle such shell-structure as is protected by overlying tissues of 

 the animal has more chance of escape than the exposed testaceous 

 coverings of Mollusca, and this will probably account for the 

 excessive rarity of this class on the Red Clay. 



I have carefully prepared two tables, '^' which I lay before you. 

 The first of these shows our present knowledge of the fauna 

 which inhabits the greatest depths on a Eed Clay bottom, and 

 the second contains a List of the Animals which have as yet 

 been observed in the North Atlantic at depths exceeding 1,000 

 fathoms. The North Atlantic has been considered in these tables 

 as extending southwards to Lat. 32° IST., that is to a line drawn 

 through Bermuda and Madeira ; but in order more effectually to 

 exclude the tropical fauna, I think it would have been better to 

 consider the North Atlantic as terminating at Lat. 35°, or a line 

 from Cape Hatteras, on the American coast, to a point just south 

 of the Straits of Gibraltar on the eastern side. The difference 

 of these three degrees, though trifling as regards the deep-sea 

 fauna, which is here alone considered, would be found consider- 

 able with respect to the shore and shallow water Invertebrata. 



A few general remarks on the fauna of depths exceeding 500 

 fathoms may not be without interest. 



Fishes. — Fish have been procured by trawl and dredge at all 

 places down to 3,000 fathoms, but in the greatest depths the 

 number of groups represented appears to be limited, and consists 

 chiefly of members of the families Mureenidse, Clupeidse, Scope- 

 lidse, Stomiatidse, Ophidiidse, Macruridse, Pediculati, and in 

 the Arctic Seas by many Lycodidce. The Mureenidse are known 

 to descend in the Atlantic to 2,500 fathoms, in the Southern 

 Ocean to 1,400 fathoms, and in the Pacific to 2,000 fathoms. 

 The Scopelidte reach 2,550 fathoms in the Atlantic, 1,950 in the 

 Southern, and 2, 150 fathoms in the Pacific Ocean. The Clupeidse, 

 as represented by Solosaurus, descend to 2,750 in the Atlantic 

 and 1,375 fathoms in the Southern Ocean. The family Stomia- 

 tidse has numerous abyssal representatives, which have been 



* These tables have been revised and filled up to the present date (August. 188"). and 

 will be found printed as Appendix B and Appendix C. 



