INTRODUCTION. 



The materials which form the subject of this Report cousisted of 794 specimens, of 

 which 610 were obtained during the voyage of the Challenger, 88 on the cruises of the 

 "Knight Errant " and " Triton," and 96 from various other sources. These specimens 

 are referred to 266 species, 177 falling to the share of the Challenger, and 14 being due 

 to the exploration of the Fseroe Channel. The number of new forms discovered by the 

 Challenger amounts to 144, whilst by the deep-sea exploration of the Fseroe Channel 

 ten species were added to the fauna of the British Seas. 



The latter possess, perhaps, the greatest interest to the student of the British marine 

 fauna; they verified the supposition which had been entertained for some time, viz., 

 that fishes distinct from those of the littoral fauna inhabit the depths of the ocean 

 surrounding the British Islands. At a time when so much attention is paid to the 

 investigation of the marine products of the British Seas, it may be hoped that the hitherto 

 intermittent efforts of exploring the deeper parts of this ocean may be prosecuted in 

 as systematic a manner as the explorations carried on on the American side of the 

 Atlantic, where the United States Government has spared no expense to secure the rich 

 harvest that was to be expected not only for the advancement of knowledge, but also 

 for the direct benefit to the country. 



The majority of the Challenger specimens were at least externally in a very good state 

 of preservation ; those fishes only which possess bones, integuments, or fin-rays of a soft or 

 delicate texture, and thin deciduous scales, naturally suffered more or less through being 

 dragged to the surface from a depth of 1000 and more fathoms. Such specimens can 

 reach the surface in perfect condition only under exceptional circumstances. However, 

 with few exceptions, even the specimens of delicate structure were sufficiently well 

 preserved to enable us to recognise their original shape and the arrangement of their 

 scales, and to reproduce them in what are believed to be tolerably accurate figures. 

 Unfortunately the abdominal organs were only too frequently found to be destroyed, or 

 had suffered too much by laceration and decomposition to admit of examination. This 

 was especially the case in those provided with an air-bladder, which was almost invariably 

 torn into mere shreds. The stomach was nearly always empty. This condition of the 

 specimens, combined with the circumstance that many of the new types were represented 



(ZOOL. CHALL. EXP. PAET LVII. 1887.) Lll ''■ 



