14 SURVEY OF LUMINOUS ORGANISMS 



from another species of all the groups, but such is not the case. No 

 luminescence appears when luciferin of Cijpridina is mixed with solu- 

 tions which should contain luciferase from copepods, or from decapods, 

 and vice versa. Only if the luciferin is from another genus of ostracods 

 (Pyrocypris) will it react with Cypridina luciferase, or will the re- 

 verse "cross" be positive. This specificity of the luciferin-luciferase 

 reaction is widespread in the animal kingdom. The chemistry of all 

 the Crustacea with external luminous secretions should be investigated 

 in detail. 



Crustacea with scattered photophores present problems of physi- 

 ological interest, but do not appear to be favorable for chemical work, 

 because of the small volume of luminous material. It is possible that 

 the photophores are hormone controlled. This relation and nerve 

 control of lighting should be carefully investigated. 



Among myriapods, the facts concerning light production of the 

 diplopod Luminodesmus has been presented by Davenport, Wootton, 

 and Gushing (1952). Chilopods produce an external secretion in 

 great abundance, which should be intensively studied. The chemistry 

 may be similar to that in earthworms, but not enough is known to 

 make a comparison. If luminous centipedes could be bred in cap- 

 tivity they should be highly favorable forms for biochemical work. 



Among insects, apart from the Coleoptera, whose luminescence 

 has been much investigated, the light of Collembola, Diptera (see 

 Kato, 1953), and the controversial genus Fulgora should be studied 

 in great detail — morphology, histology, physiology, and chemistry. 

 Very little is known of light production in these rather uncommon 

 luminous insects. 



That fireflies have been of great value for biochemical work is 

 apparent from the report presented in another section. The rapid 

 flash of a firefly still remains an unsolved problem in insect physiology. 

 Behavior studies in different species of fireflies in regard to the 

 use of the light (see Buck, 1937, 1948), present a promising field for 

 the ecologist. The meaning and mechanism of synchronous flashing 

 of tropical fireflies is still a mystery. Finally the spectral energy distri- 

 bution of the light of various species should be explained. Since 

 Coblentz' monograph of 1912, httle has been done to determine 

 whether the range in color of the light from orange to yellow green 



