MUSEUM OF COMPARATIVE ZOOLOGY. 103 



No. 6. — Contributions to the Fauna of the Gulf Stream at great 

 depths. By L. F. de Pourtales, Assist. U. S. Coast Survey. 



(Communicated bt tiie Superintendent of the U. S. Coast Survey.) 



The study of the constitution and of the inhabitants of the bottom of 

 the sea is a field of research which has attracted the attention of natural- 

 ists in comparatively recent times. What Humboldt did with regard 

 to the distribution of life at different heights in the atmosphere, was 

 done by Edward Forbes for the different depths of the ocean. The 

 former's diagrams of the zones of vegetation on the slopes of the Andes 

 are considered indispensable in every atlas of physical geography. 

 But what one man could do where his glance embraced miles of coun- 

 try in height and breadth and where the types of vegetation could 

 frequently be recognized as far as the eye could reach, an investigator 

 even as zealous as Forbes could but sketch in broad though happily 

 drawn lines for the marine animals. 



Much has been done in this direction since Forbes's death, particu- 

 larly in England, where dredging has become a favorite occupation of 

 many naturalists ; the Scandinavian seas have also been explored with 

 much success, chiefly by the Norwegian naturalists ; but much more 

 remains to be done in a field in which the areas to be explored can, 

 as Jeffreys remarks, be reckoned in square degrees, whilst the research 

 extends only over square yards. 



It is particularly in the greater depths, in the so-called abyssal 

 region, that our knowledge is deficient. This is easily understood, since 

 on many coasts the sea is comparatively shoal for a considerable dis- 

 tance from land, and the outfit for deep-sea dredging is beyond the 

 means of but few private individuals. Government expeditions are 

 generally fitted out for other duties, and can rarely devote their time to 

 operations occasioning a delay of many hours. Furthermore, owing 

 to the scantiness of the material, the impression generally prevailed, 

 until recently, that animal life was soon reduced to a minimum with 

 an increase of depth, or at least reduced to the lowest forms, so that 

 the incentive of a rich harvest seemed denied to those who would have 

 undertaken such researches. 



