Shining Fish, Flesh, and Wood 505 



Kryptogarnen " in the greasy luminous mass on hog flesh or fish. 

 He tested many substances to find out their efi:ect on the light but 

 added nothing new to the knowledge of the day. Under an air 

 pump, the light of the luminous material became very weak but 

 on readmitting air " blitze er plotzlich wieder auf." Hankel was 

 surprised to find that in pure oxygen or in ozonized oxygen the 

 light failed to increase in brightness. C. Home (1869 reported a 

 dead luminous lobster with no mention of bacteria, and even as 

 late as 1871, P. Panceri, the great Italian student of bioluminescence, 

 in a study of luminous fish, attributed the luminescence to the 

 oxidation of fat. 



It is fitting that for all practical purposes the history of knowledge 

 of shining wood, fish, and flesh should end with Eduard Pfliiger, a 

 pupil of Karl Ludwig (1816-1895) and the founder of the Archiv 

 fiir die gesamte Physiologic in 1868, one of the foremost physiolo- 

 gists of Germany. Pfliiger is also a good example of a scientist who 

 made one important contribution to bioluminescence and then be- 

 came interested in other things. The study of luminous fish in his 

 two papers (sixty-six pages in all) was a direct consequence of early 

 interest in cell oxidation. It was Pfliiger who showed in 1872 that 

 the blood was not the place where oxidation of foodstuff took place, 

 as had been generally supposed, but that they burned in the muscles 

 and other cells of the body. 



After Pfliiger's papers, publications were largely concerned with 

 characterizing and naming the various species of luminous bacteria. 

 Two years later, J. Nuesh (1877) spoke of Bacterium lucens (1877) 

 and Bacterium termo (1879) , F. Cohn (1878) of Micrococcus phos- 

 phorens, and O. Lassar (1880) of Micrococci, confirming Pfliiger's 

 work. In 1884 F. Ludwig described Micrococcus Pflugeri, and O. 

 Katz (1887, 1891) a number of new species. 



Other workers are too numerous to mention, but three names of 

 the nineteenth century should be remembered as preeminent, that 

 of B. Fischer (1852-1915) , a ship's medical officer, later professor of 

 hygiene in Kiel, who noted the world-wide distribution of luminous 

 bacteria in 1887, 1888 and 1894, that of M. W. Beijerinck (1851- 

 1931) , the great Dutch bacteriologist of Delft, who greatly advanced 

 biochemical knowledge from 1889 to 1915, and F. Ludwig, whose 

 studies of the light of both bacteria and fungi extended from 1874 

 to 1904. 



Investigation of luminous wood and fungi in the last half of the 

 nineteenth century was concerned chiefly with descriptions of new 

 luminous species and attempts to culture the mycelium from lumi- 

 nous wood. F. Ludwig was the pioneer in this field, ably followed 



