DEPARTMENT OF MARINE BIOLOGY. 167 



Agricultural College at Tokyo, Japan, have been received from time to time, 

 and it gives me great pleasure to acknowledge the kindness and interest of 

 Professor Ishikawa in supervising the collection of this material for me. 

 Cypridina is by far the most favorable organism for chemical research, and 

 a source of supply in this country is much to be desired. If an abundant 

 supply of these organisms were available, the chemical nature of luciferin, the 

 substance oxidized with light production, could unquestionably be worked 

 out and its synthesis possibly accomplished. 



Such abundant stock of Cypridina is not at present available, and accord- 

 ingly I have directed the research along three lines which do not require so 

 large an amount of material, viz : 



(1) Studies on the specificity of luciferin and lucif erase, to ascertain whether 

 the luciferin of one species of luminous animal will give fight if mixed with 

 the luciferase of another species, and vice versa. 



(2) Studies on the methods of reduction of oxyluciferin to luciferin. By 

 this means luciferin can be regenerated from its oxidation product, oxyluci- 

 ferin, and continuous luminescence produced. 



(3) Studies on the kinetics of the luciferin 7— oxyluciferin reaction. This 

 problem has been ably investigated by Dr. William R. Amberson, and his 

 resume of the work follows. 



The full papers embodying the above investigations will be published during 

 the year in the following journals: 



Harvey, E. N., Studies on bioluminescence: XIV. The specificity of luciferin and luciferase. 



Jour. Gen. Physiol., vol. 4, 285-295 (1922). 

 Harvey, E. N., Studies on bioluminescence: XV. Electro-reduction of oxyluciferin. Jour. 



Gen. Physiol. (1922). 

 Amberson, Wm. R., Kinetics of the bioluminescent reaction in Cypridina, I and II. Jour. Gen. 



Physiol., vol. 4, 517-558 (1922). 



The complete account of the author's work on the luminous fish of the 

 Banda Islands, Photoblepharon and Anomalops, will appear in the forthcom- 

 ing volume of Contributions from the Tortugas Laboratory. 



Specificity of Luciferin and Luciferase. 



Cypridina luciferin has been mixed with extracts of 14 different groups of 

 luminous animals, so prepared that they should contain the luciferase of 

 each group. These groups were: (1) cystoflagellates (Noctiluca) ; (2) penna- 

 tulids; (3) medusae; (4) ctenophores; (5) odontosyllid worms; (6) polynoid 

 worms ; (7) chaetopterid worms ; (8) polycirrid worms ; (9) schizopod Crustacea 

 (Meganyctiphanes) ; (10) fire-flies; (11) mollusks (Pholas); (12) ascidians 

 (Pyrosoma); (13) balanoglossids (Ptychodera) ; (14) fish (Photoblepharon). In 

 no case did light appear. Cypridina luciferase has also been mixed with 

 extracts of the above 14 groups, so prepared that they should contain the 

 luciferin of each group. In no case did light appear. It is, therefore, con- 

 cluded that luciferin and luciferase of various forms are specific to a high 

 degree and will not react with luminescence if produced by unrelated animals. 

 If the relationship is close, luminescence will appear. Thus, Cypridina 

 luciferin will react with the luciferase of Pyrocypris, another genus of ostra- 

 cods, and vice versa. We must, therefore, consider the luciferins or luci- 

 ferases to be a group of chemical substances, differing slightly in different 

 orders of animals as do the hemoglobins of different vertebrates. 



