586 History of Luminescence 



of Crustacea, the decapods, the schizopods or euphausids, and the 

 mysids. The animals usually occur in great schools at medium depths 

 and frequently migrate to the surface at night. The old names. 

 Cancer, Gammarus, and Oniscus were applied to these shrimp-like 

 Crustacea and it is possible that the Oniscus fulgens of J. Anderson 

 (1746), observed during his trip to Iceland and Greenland, was a 

 schizopod rather than the copepod, Sapphirina, as Meyen (1834) 

 believed. Before Macartney's paper on luminous animals appeared 

 in 1810, he was given permission to inspect the journal of Sir Joseph 

 Banks, kept during his trip with Captain Cook in 1768-1771, and to 

 copy some of the original drawings of luminous animals. One of 

 these is the Cancer fulgens, apparently a schizopod, reproduced in 

 figure 47. 



Tilesius (1819) also figured shrimp-like luminous animals. It 

 is quite certain that the luminous crustaceans mentioned by J. V. 

 Thompson (1829) as Cynthia, Noctiluca, Lucifer, and Podopsis, and 

 the one figured by W. Baird (1831, were mysids or euphausids. 

 Later, many marine collecting expeditions saw luminous shrimp, 

 and during the U. S. Exploring Expedition of 1838-1842, J. D. Dana 

 (1852) described both luminous schizopods (Euphausia splendens) 

 and luminous decapods (Regulus lucidus) . 



Many of the luminous shrimp possess definite light organs, first 

 called "luminous globules" by G. O. Sars (1837-1927) in 1885. 

 They contain a lens and structures somewhat similar to the eye, 

 hence were called accessory eyes by Carl Claus (1835-1899) in 1863. 

 The first important histological study was by R. Vallentin and J. T. 

 Cunningham in 1888, followed by a number of other papers by 

 various writers. 



In contrast to shrimp possessing luminous dots or photophores, 

 the most interesting of the decapods are the species living in the 

 deep sea and having the ability to produce great masses of luminous 

 secretion with which they surround themselves whenever disturbed. 

 These forms were first caught by A. W. Alcock and described in his 

 book A Naturalist in Indian Seas (1902) . 



Sometimes shrimp become infected with luminous bacteria. The 

 most remarkable case of this kind, because living infected animals 

 can be regularly obtained, has been described by Y. Yasaki (1927) , 

 who demonstrated the presence of the bacterial organisms and grew 

 them in pure culture. Knowledge of the shrimp, a species of Xipho- 

 carida, living in Lake Suwa, Japan, comes from a Mr. Ushiyama 

 who first noticed them in 1914. 



