Animal Luminescence 577 



is so bright as to be discoverable even in open Daylight, especially 

 on being touched or disturbed." 



According to Panceri (1875) , luminous worms were seen by Pehr 

 Osbeck (1757) on a trip to China in 1750-1753 and Job Raster in 

 1757 published a careful drawing of several varieties. In the tenth 

 ediiion oi Linnaeus' Systema Naturae (1758) , Nereis noctiluca (the 

 Noctiluca marina of Adler) is mentioned, as well as the " Scolo- 

 pendre marine luisante " of Grisellini and the " Lucioletta dell'aqua 

 marina " of Vianelli. The discoveries continued, with Peter Forskal 

 (1736-1768) in 1775 describing luminous worms called Nereis 

 coerulea, N. pelagica, and N. viridis from the Kategat, Otto Fabri- 

 cius (1744-1822) in 1780 with a luminous Nereis noctiluca from 

 Greenland and Lazaro Spallanzani (1729-1799) with luminous 

 marine worms at Portovenere near Genoa in 1784, which he de- 

 scribed in a letter to Charles Bonnet (1720-1793) . Domenico Vivi- 

 ani (1805) in Phosphorescentia Maris again described and figured a 

 number of annelids from the seacoast near Genoa. 



It is obvious that luminous annelids are widely distributed in 

 various seas. Some eight families of polychaetes are now known to 

 produce light. Of great interest are the transparent, pelagic forms 

 of the genus Tomopteris, not known to be luminous until R. Greeff's 

 observations in 1882. The lighting ability of terebellid worms was 

 recognized by Adolf Grube (1812-1880) in 1861. 



Luminescence of the genus Chaetopeterus, living throughout life 

 in an opaque parchment tube, buried in the mud, yet brightly lumi- 

 nescent from a slime secreted over most of the external surface, 

 appears to have been first seen by F. Will at Trieste in 1844. Chae- 

 topterus is also of note as the first luminous marine form, whose 

 spectrum was observed, by E. Ray Lankester in 1868. 



The physiology and histology of a number of marine annelids has 

 been studied by A. de Quatrefages (1843), by P. Panceri (1878), 

 by W. A. Haswell (1882) , and Et. Jourdan (1885) , pioneers in the 

 investigation of luminescence in this group. Quatrefages, of Nocti- 

 luca fame, began his luminescence work with polynoid worms and 

 ophiurians in 1843, and it was these animals which led him to 

 announce the connection between luminescence and contractility. 

 In fact, he thought that the light of the polynoid worm actually 

 came from the muscles, while Panceri (1878) regarded nerves as 

 the source of the light. Both mistakes were rectified by Jourdan in 

 1885. 



The Piddock or Dail (Pholas dactylus) 



The publicity which Pliny gave to the ungues or finger nails, the 

 shellfish which " shine as if with fire in dark places, even in the 



