The Nineteenth Century 231 



ter of Volume 8 (1863) is devoted to " Production de lumiere par 

 les animaux," with approximately 130 references to all the known 

 studies on luminous animals of the time. Milne-Edwards divided 

 the work into " Phosphorescence due a la putrefaction," " Phospho- 

 rescence physiologique "—the latter observed in Insectes, Myria- 

 podes, Crustaces, Les Vers, Mollusques, Zoophytes— and " Phospho- 

 rescence de la mer " which is correctly attributed to Noctiluques 

 and other small organisms. Regarding the phosphorescence of putre- 

 faction (dead fish and meat) , Milne-Edwards believed it to be due 

 to the formation of small quantities of hydrogen phosphide, from 

 the action of nascent hydrogen on decomposing organic phosphorus 

 compounds, which burned in the air. The light which appeared at 

 night from wet sandy beaches might also be due to putrefaction but 

 Milne-Edwards admitted that in the present state of science there 

 was not a satisfactory explanation of light emission by living ani- 

 mals. In some cases it was thought to be due to the secretion of a 

 material susceptible of becoming luminous in contact with oxygen, 

 whereas in other cases the luminescence did not appear to arise in 

 the same manner. 



Toward the end of the century the medical physiologies ^^ omitted 

 any account of bioluminescence but the subject was taken up in the 

 general physiologies,^- of which Max Verworn's (1863-1921) Allge- 

 meine Physiologie became widely known. It appeared in 1894, with 

 a second edition in 1897, translated into English by F. S. Lee in 

 1899. The section dealing with " Die Production von Licht " was 

 completely modern and compared the emission of light by living 

 things to the chemiluminescences discovered by Radziszewski in 1877 

 to 1883. 



Among the many plant physiologies of the nineteenth century, 

 some of the older works discussed " The Development of Light," but 

 only Wilhelm Pfeffer (1845-1920) in his great Handbuch der Pfian- 

 zenphysiologie, which first appeared in 1880, has adequately treated 

 plant luminescence in a special section. In Vol. 3 of A. J. Ewart's 

 translation (1900), six pages are devoted to "The Production of 

 Light " with a considerable number of bibliographical references. 

 The account is excellent, with modern treatment of both bacteria 

 and fungi, and reference to the luciferin and luciferase of R. Dubois 

 (see a later section) , as well as to inorganic luminescences. In the 



*^ These include such famous works as those of L. Hermann (1879-1883) , John C. 

 Dalton (1882) , M. Foster (1877) , E. A. Schafer (1898) , and the American text-book o) 

 physiology (1896) , by several authors. 



^- One of the earliest of these was the Principles of general and comparative physi- 

 ology (1839) of W. B. Carpenter (1812-1885), who also wrote on the microscope in 

 1856. The Principles (1854 ed.) contains a good section on " Evolution of light." 



