BIOLUMINESCENCE IN BACTERIA 379 



It is noteworthy that in the Vegetable Kingdom the pheno- 

 menon of bioluminescence is never exhibited by any of the green 

 plants — Algae, Bryophyta, Pteridophyta, and Phanerogamia — but 

 is limited to the brown Peridinieae and to Bacteria and Fungi, non- 

 chlorophyllous plants, which are either saprophytes or parasites 

 and carry on their metabolism in a manner approaching that 

 of animals. Bacteria and Fungi, as is well known, cannot perform 

 the function of photosynthesis but obtain their energy, as do 

 animals, from complex organic compounds. Furthermore, Fungi, 

 in the production of such substances as chitin, glycogen, urea, 

 sarkin, cetylalcohol, and cerebrosin, and in the non-production of 

 chlorophyll, starch, and cellulose, show distinct chemical resem- 

 blances to animals.* It seems probable that the photogen con- 

 tained in luminescent fungi is essentially the same as that of 

 luminescent animals. Should future investigation prove that this 

 supposition is correct, one further chemical resemblance between 

 fungi and animals will have been established. 



The best known forms of light-producing animals are : the dino- 

 flagellates ; Noctiluca ; hydroids ; jelly-fish ; ctenophores ; sea pens ; 

 Chaetopterus and other marine worms ; earth-worms ; brittle stars ; 

 various crustaceans ; myriapods ; fireflies and glow-worms, the 

 larvae of fireflies ; the molluscs Pholas dactylus and Phyllirrhoe 

 bucephala ; squids ; Pyrosoma, a colonial ascidian ; and fishes. ^ 



Luminous fungi and bacteria, as well as a few fish, give off light 

 continuously and independently of stimulation. Noctiluca and most 

 animals give off light only when they are stimulated. ^ 



It is believed by Pierantoni (1918) and Paul Buchner (1921) 

 that the luminescence of Fireflies, Cephalopods, and Ascidians 



1 For the chemistry of the Higher Fungi vide J. Zellner, Chemie der Hoheren 

 Pilze, Leipzig, 1907. Chitin occurs in the cell membranes of most fungi. Glycogen 

 is found in Yeast cells, young asci, young basidia, etc. Urea has been obtained from 

 Lycoperdon Bovista and L. gemmatum (Zellner, pp. 53-54). Sarkin has been obtained 

 from Fuligo septica (Zellner, pp. 54, 235). Cetylalcohol occurs in Fomes officinalis 

 (Zelhier, pp. 20, 21, 39). Cerebrosin, which occurs in the brain and spinal column 

 of animals, is believed to have been extracted from Lycoperdon Bovista (Zellner, 

 p. 193). 



2 E. N. Harvey, The Nature of Animal Light, Philadelphia and London, 

 1920, p. 10. 



3 Ibid., p. 69. 



