SOME CONSIDERATIONS CONCERNING THE 

 PHOTOGENIC FUNCTION IN MARINE 

 ORGANISMS 



F. ALEX. McDERMOTT 

 Washington, D. C. 



In two very interesting papers, Professor C. C. 

 Nutting 1 has brought forth evidence tending to show that 

 in oceanic depths below the range of penetration of the 

 sun's rays, there exists a dim, phosphorescent light, quite 

 general in its distribution, radiated from various photo- 

 genic organisms of the abyssal regions, and having a defi- 

 nite and valuable significance for the life of animal forms 

 at these depths. 



That such a light actually exists is scarcely to be sanely 

 doubted, in view of the evidence of the deep-sea explora- 

 tions which have added so much to the knowledge of 

 oceanic conditions. And that it has a purpose in the life 

 of the forms inhabiting those portions of the ocean beds 

 where it exists, seems to the writer equally undeniable, 

 unless we accept Emerson's poetic reasoning that 



"Beauty is its own excuse for being." 



Just what its purpose may be in hermaphroditic, simple 

 forms not provided with definite organs of sight, and 

 indeed also in many higher forms, may, of course, still be 

 a legitimate subject for investigation and consideration. 



Professor Nutting's remarks have been of special 

 interest to the writer in connection with some recent 

 studies made by the latter on the general subject of bio- 

 photogenesis, with special reference to the- Lampyridne.- 



l (o) "The Utility of Phosphorescence in Deep-sea Animals," Amice. 

 Nat., Vol. 3, 1899, pp. 792-799; (ft) "The Theory of Abyssal Light," 

 Proc. VII Cong. Zool., advance reprint, 1910. 



2 Amer. Joum. Physiol., 1910 Vol. 27, pp. 122-151; Canad. Entomol., 

 1910, Vol. 42, pp. 357-363; Popular Set. Monthly, 1910, Vol. 77, pp. H 4 " 

 121. 



118 



