70 



CHAP. VI. 



PHOSPHORESCENCE OF THE OCEAN CONTINUED. 

 VARIOUS SOURCES OF LIGHT CONNECTED WITH 

 MARINE ANIMALS. LUMINOUS SEAWEED. LUMI- 

 NOUS TESTACEA. SPECIFIC DIFFERENCES IN THE 



PHOSPHORESCENCE OF THE OCEAN. VARIOUS 



ANIMALS CONTRIBUTING TO THIS LUMINOSITY. 



THIS INVESTMENT OF LIGHT A BENEFICENT PRO- 

 VISION. 



CAPTAIN HOME, It. N., communicates to the editor 

 of the Quarterly Journal of Science the fact, that the 

 cause of the brilliant light observed in the sea weed 

 thrown on the beach at Lancing, on the coast of 

 Sussex, is the Sertularia volubilis of Ellis, or the 

 Clytia volubilis of Lamouroux, not however described 

 as luminous : it is evident, therefore, that this animal, 

 if it be not invested with a constant light, becomes 

 at any rate luminous under peculiar circumstances. 

 On the 8th of December last, and three following 

 days, a hard blowing S.W. wind cast a considerable 

 quantity of sea weed on the beach, which was 

 covered with it to the depth of more than two feet 

 in some places. A small quantity of the most bril- 

 liant was collected at night, and this appears to have 

 been invariably that left at the first of the ebb. By de- 

 taching a luminous speck, Captain Home ascertained, 

 by the aid of the microscope, that this was occasioned 

 by adhering insects. The light would sometimes 

 remain steady for about five seconds, often less, and 

 when it ceased, was renewed by the contact of the 



