266 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 3 2 



of the bottom samples have been collected b)'^ the Asterias, a 40-foot 

 I^ower boat also operated by the institution. But during April, 

 1932, two lines of stations were run by the Atlantis off the New Jersey 

 coast with samples taken every 2 miles from the beach to the 1,000- 

 fathom curve. By studying the distribution of the various sized 

 particles composing the mud, it is hoped that something will be 

 learned about the depth of wave action and the geologic history of 

 the formation of the continental shelf. 



The physical program of the Atlantis has not been so extensive 

 that some valuable biological investigations could not be carried out 

 at the same time. During much of the year it has been the custom 

 to make a tow for eel larvae every second evening when the vessel 

 was cruising in suitable regions. These tows were made to collect 

 eel larvae for the Carlsberg Laboratory in Copenhagen. Through 

 a study of the distribution and sizes of the young eels, their migra- 

 tion route from the spawning region south and east of Bermuda has 

 been mapped out, and since their long journey back to Europe is 

 much dependent on the currents, the eel tows are valuable to physical 

 oceanographers because the eels make excellent drift-bottles. At the 

 same time, a general collection of oceanic plankton has been carried 

 out for the laboratory at Bermuda, which will eventually show 

 more clearl}^ tlio distribution of the various small floating animals 

 found near the surface in the central North Atlantic. 



The Atlantis's heavy winch with its 5 miles of cable was intended 

 mainly for handling large deep-sea nets and dredges. Her cruises 

 to date have not included any program of bottom dredging, but 

 enough deep-sea tows have been made to test the machinery thor- 

 oughl3\ These tows have advanced the technique of handling large 

 nets, besides being instructive in the problem of bringing up deep- 

 sea fish in good condition. There is even reason to expect that in 

 regions where the surface waters are not too warm, deep-sea animals 

 can be brought to the surface alive, if proper precautions are taken. 

 The cod end of the nets must be lined with some soft material so 

 that the fish will not have their skin chafed oif by the rush of water 

 through coarse netting and the hauling speeds must be so regulated 

 that the animals have time to " decompress " on the way to the sur- 

 face. The difficulty is that fish living normally in waters having 

 a temperature of 4° C. will be killed by being brought through the 

 surface layers which are usually very much warmer. It would seem 

 that in winter, if tows were made in the northern seas, this difficulty 

 might be eliminated and the fish brought back alive. 



The question of the penetration of light below the sea surface 

 and its effect on the animal life in the upper layers of the ocean 

 has recently received considerable impetus through the development 



