382 THE PRODUCTION OF HEAT, LIGHT, AND ELECTRICITY 



PART II 

 THE PRODUCTION OF LIGHT 



SECTION 84. Instances and Causes of Luminosity. 



Like many animals 1 , certain plants are self-luminous, such as many 

 Bacteria, Fungi, and the chlorophyllous Ceratium tripos 2 . Among Fungi, 

 it is usually the fruit body of Hymenomycetes or Ascomycetes that is 

 luminous, but the mycelium may also be luminous and cause, for instance, 

 the luminosity of wood attacked by Fungi. The so-called phosphorescence 

 of fish and of meat is due to the activity of Bacteria. 



The glow is usually feeble like that of moist phosphorus in darkness, 

 but Gardner states that in Brazil a few specimens ofAgaricus Gardner* gave 

 out sufficient light to read print 3 . The rays from luminous Bacteria are 

 able to produce heliotropic curvatures or even the production of chloro- 

 phyll 4 , and to enable the organisms to photograph themselves on a sensitive 

 plate 5 . 



Bacteria. Pfluger showed that the phosphorescence of meat was due to Bacteria, 

 and Bacterium phosphorescens, B. Pfliigeri, B. indicum, and B. luminosum are all 

 strong!/ luminous species 6 . Certain forms are always present in sea-water, and 

 hence the readiness with which moist fish, or moistened smoked haddock, becomes 

 luminous when hung up in a fairly cool room. In the same way a piece of flesh 

 partially immersed in a saline solution will usually become luminous owing to the 



1 Cf. Dubois, Le?ons de Physiol., 1898, p. 301 ; Verworn, Allgem. Physiol., 3. Anfl., 1901, 

 p. 263; de Kerville, Die leuchtenden Thiere u. Pflanzen, German translation by Marshall, 1893. 



2 J. Reinke, Wiss. Meeresunters. d. deutschen Meere, 1898, N. F., Bd. in, p. 39. 



3 Gardner, Flora, 1847, p. 756. Good cultures of phosphorescent bacteria give out sufficient 

 light to enable one to tell the time by a watch at night. 



4 Molisch, Sitzungsb. d. Wiener Akad., 1902, Bd. cxi, Abth. i, p. 141 ; Isatschenko, Chloro- 

 phyllbildung im Bacterienlicht, Centralbl. f. Bact., 1903, Abth. ii, Bd. x, p. 498. 



5 Forster, Centralbl. f. Bact., 1887, Bd. II, p. 338; B. Fischer, ibid., 1888, Bd. in, p. 140; 

 Molisch, Sitzungsb. d. Wiener Akad., 1903, Abth. i, Bd. cxir, p. 297. 



6 Pfliiger, Archiv f. Physiol., 1875, Bd - x P- 2 755 Bd - XI > P- 22 3- cf - Molisch, Bot. Ztg., 

 Orig., 1903, p. i. For nomenclature see Migula, System d. Bacterien, 1897, Bd. I, p. 336; 

 B. Fischer, Zeitschr. f. Hygiene, 1887, Bd. n, p. 54; Centralbl. f. Bact., 1888, Bd. in, pp. 105, 137 ; 

 1888, Bd. IV, p. 89; Beyerinck, Archives Neerlandaises, 1889, T. xxm, pp. 104, 367, 416; 1891, 

 Bd. XXIV, p. 369 ; Koninklijke Akad. v. Wetenschappen te Amsterdam, Proceedings of the Meeting, 

 27. Oktob., 1900, p. 359; Lehmann, Centralbl. f. Bact., 1889, Bd. v, p. 785 ; Kutscher, ibid., 1890, 

 Bd. VIII, p. 124; Katz, ibid., 1891, Bd. IX, p. 157; C. Eijkmann, ibid., 1892, Bd. xil, p. 656; 

 Suchsland, ibid., 2. Abth., 1898, Bd. IV, p. 713 ; Tarchanoff, Compt. rend., 1900, T. cxxxi, p. 246 ; 

 McKenney, Obs. on the cond. of light production in Bacteria, 1902, reprint from Proc. of the Biol. 

 Soc. of Washington, Vol. xv, p. 213 ; Barnard and Macfadyen, Annals of Botany, 1902, Vol. XVI, 

 p. 387. A summary is given by Migula, System der Bacterien, 1897, Bd. I, p. 336 ; Fliigge, Mikro- 

 organismen, 3. Aufl., 1896, Ed. I, p. 166. 



