804 THE ZOOLOGIST. 



EARTHWORM STUDIES. 



By the Rev. Hilderic Friend, 



Author of ' Flowers and Flower-Lore.' 



III. Phosphorescence and Luminosity. 



Among the various members of the Animal Kingdom which 

 possess the power of emitting a phosphorescent glow are certain 

 inhabitants of Wormland, to some of which we wish to draw 

 attention. The notice of the public, so far as my researches 

 show, was first directed to the subject in the year 1670 by 

 Grimm; but scientific observation was then scarcely known. 

 Later came Flauguergues in 1780; his paper on the phosphores- 

 cent light of Earthworms appearing in ' Lichtenberg's Magazin ' 

 in the German language. It may also be seen under the French 

 title "Sur la Phosphoresine des Vers de terre " in 'Rozier Journ. 

 de Phys.,' xvi. (1780) pp. 311-313. In 1873 Cohn's observations 

 on the same subject were published in the ' Zeitschrift fur 

 Wissenschaft. Zoologie,' vol. xxiii. pp. 459-461, and entitled 

 " Leuchtende Regenwurmer " ; while numerous recent writers 

 have further contributed to our knowledge, especially in relation 

 to the continental species. Thus in 1872 an article appeared in 

 the French ' Ann. Sci. Nat.' ser. 5, t. xvi. by Panceri, entitled 

 " Etudes sur la phosphorescence des animaux marins," in which 

 he states that the luminosity observed in the case of certain 

 worms is due to a secretion from the girdle where special glands 

 exist, and that with the evolution of light there was no perceptible 

 raising of the temperature. In this respect, therefore, the glow 

 corresponds with that emitted by the Firefly, Noctiluca, and 

 Glowworm. One investigator at least has tested the colour and 

 composition of the luminosity by the spectroscope, and says that 

 it is not unicolored or monochromatic, but compounded chiefly 

 of the red and violet rays. Other students regard the substance 

 which produces the light as homogeneous. 



