INTKODUCTION. V 



has occurred five times. On the other haiul, Chia.imodoti, although so abnudant, has only 

 once been taken by the deep sea nets. 



Another ocean dweller which the exploring ships have not yet discovered is 

 Rei/aleeu.s, or the '* Oar- fish," a serpent shaped, rapidly swimming form, nsiially from 18 

 to 24 feet in length, which occasionally is stranded on the shore in the stormy season. 

 Within the past one hundred and fifty years individuals have visited the shores of Nor- 

 way, Finniark, the Faroe Islands, Scotland, Ireland, England, JNFediterranean, France, 

 Bermuda, the Cape of Good Hope, Hindustan, and Xew Z(>alan(l. (iiinther gives a list 

 of 44 seen by naturalists, and this is of course but an insignificant part of those which 

 have actually b'een stranded. Its worldwide distribution and the number of waifs give 

 evidence that it is abundant in mid-ocean, yet the exploring ships in all the years of their 

 combined searchiugs have found no vestiges of it, old or young. 



Many similar cases might be cited, but our object is simi)ly to call attention to the 

 great necessity for further exploration of the depths. 



The distinctions between the inhabitants of deep water, those of the middle depths, 

 and those of the surface strata of mid-ocean are not yet absolutely fixed. Such are the 

 imperfections in the methods of trawling and dredging that the naturalist, when he has 

 sorted out the tishes from his nets after a haul in mid ocean, is often in doubt as to where 

 his captures have been made. If he has taken a flounder from a haul of 800 fathouis, or 

 finds a niacrurid, a brotulid, a stomiatid, a synodontid, or a nemichthyid in a net which 

 has been below the 2,000-fathom line, he feels reasonably sure that he has brought it up 

 from the bottom. But who shall say where Arfji/ropclccus, Sfenwptyx, Myctophum. having 

 allies among the pelagic fishes in the same net, have come from? It may be from the 

 bottom, or they may have become entangled in the meshes of the trawl when but a few 

 fathoms from the surface, coming uj) or going down. 



The recent investigations of Mr. Agassiz in the Pacific, with the Tanner net, seem to 

 show pretty conclusively that there are but few living forms below a depth of 1,800 or 2,000 

 feet and tliat the Myctophidw stay for the most part, if not entirely, between that depth and 

 the surface. It is possible to draw inferences from the experiments in regard to many forms 

 which, like the Mi/ctophidw, are known frequently to occur swinuuing at the surface at 

 night, but there are also doubtful cases, like Bathyophix, Rhodichtliys, Microstoma, and many 

 others, which need further consideration. 



Another great need is for more, and more perfect, material. Fully one-half of the deep- 

 sea forms are now represented only by single specimens, and many important anatomical 

 questions can not be solved, because these unicjues may not be sacrificed to dissection. Half 

 of the families of Malacopterygians mentioned in this report can not be assigneil to their 

 proper places, because their skeletons have not been fully examined. 



Besides this, the imperfection of the existing specimens is a great drawback. The 

 material is of a kind which it is peculiarly difficult to study. Not only are the forms 

 strange and difficult to assign to their i)roper taxonomic relationships, but, owing to the 

 soft, cavernous skeletons, and the flabby muscles, tender skins, deciduous scales, and fragile 

 appendages which are characteristic of many of them, they are very liable to injury. After 

 these delicate animals have been drawn up from a depth of 2 or 3 miles in rough nets, they 

 are, as might be expected, in a very dilapidated condition. It has often been found neces- 

 sary to examine a score of more of individuals, in order to be able to appreciate characters 

 which could commonly be made out from a single specimen. 



The studies which have led to the writing of this book were begun in the sumnun- of 

 1877, when the first deep-sea fishes were caught b}^ American nets on the coast of North 

 America. This took place iu the Gulf of Maine, 44 miles east of Cape Ann, on the 19th of 

 August, when from the side of the U. S. Fish Conunission steamer Sprcdiccll the trawl net 

 was cast in 100 fathoms of water. The writers were both standing by the mouth of the net 

 when, as the seaman lifted the end of the bag, two strange forms fell out on the deck. A 

 single glance was enough to tell us that they were new to our fauna, and probably unknown 

 to science. They seemed like visitors from another world, and none of the strange (bruis 



