Glowing-ball- or globe-type displays are seen most freq.uently in the 

 warmer waters of the world. The ocean may appear as if full of balls or 

 discs of light, some flashing brightly as they are disturbed and others 

 dimming after the initial stimulus has ceased. The flashes or pulsations 

 of light may range in size from a few centimeters to a niimber of meters 

 in diameter, depending upon the size of the organisms. The light given 

 off usually is blue or green; occasionally, displays of white, yellow, 

 orange, or red have been reported. The light rarely is continuous and 

 may be noted from afar by its flashing appearance. 



Combinations of either two or all three types of displays often occur. 

 The light given off may consist of flashing luminescence against a cloud- 

 like luminescence in the water or a mixtiire of glowing-ball- and sheet- 

 type luminescence. In some observations, especially in higher latitudes, 

 the scintillations of luminous crustaceans may be seen as they graze on 

 the edges of large concentrations of luminous dinoflagellates, that is, 

 a spark-type display fringing on a sheet-type display. 



Exotic light formations like "phosphorescent wheels, " undulating waves 

 of light, and bubbles of light appear to be separate and distinct from 

 all three types discussed above. "Phosphorescent wheels" and "waves" of 

 light are discussed in another section. 



OBSERVATION REPORTS 



In preparing the charts used in this report the writer had access to 

 files in the Biological Section of the U. S. Naval Oceanographic Office 

 containing approximately 3^000 individual reports of displays throughout 

 most of the oceans of the world. These reports date primarily from the 

 beginning of the 19th centaury to the present time; however, a few reports 

 are many centuries old, and these have been included in the overall pres- 

 entation where they were considered usefiil. 



Most of the reports of displays have been obtained from publications 

 such as the British "The Marine Observer," the "Hydrographic Bulletin" 

 of the U. S. Wavy Hydrographic Office, and the "Notices to Mariners" 

 published jointly by the U. S. Coast Guard and the U. S. Naval Oceano- 

 graphic Office. In addition to the above publications, numerous scientific 

 cruise reports, especially narrative logs, provided many reports. Reports 

 from books of ocean travels also were included. The works of Harvey (1952), 

 Nicol (i960), and Tarasov (195^) were of special value. 



As with many types of oceanographic and hydrographic data, a bias 

 exists in the geographic distribution of bioluminescence observations, 

 inasmuch as the majority of reports axe from frequently traveled shipping 

 lanes. Consequently, reports of displays were unavailable or few in 

 number for many regions. When the available reports are all plotted, they 

 may give an erroneous representation of the seasonal distribution of bio- 

 luminescence in many places. Therefore, additional infonnation such as 

 published general descriptions of bioluminescence, ecological factors, 

 distribution of organisms causing bioluminescence, and many other types of 

 miscellaneous data were used to provide a more comprehensive coverage of 

 the phenomenon. 



