OBSERVATIONS ON LUMINOUS ANIMALS. 349 



of the sea around this country ; and by comparing the ac- ness of the sea. 

 counts of others with each other, and with what I have iny- M'st^ken for 



■' ■' tile nereis noc- 



self seen, 1 am persuaded, that it is so likewise in other parts lUuca by some ; 

 of the world. Many observers appear to have mistaken J^'^'^'^5'^'^''''^'*, 



, , by others, who 



this species for the nereis nocHluca, which was very natu- were not crwase 

 tural, as they were prepossessed with the idea of the fre-"^^*-^ nature, 

 quent existence of the one, and had no knowledge of the 

 other. Some navigators have actually described this species 

 of medusa, without being aware of its nature. Mr. Bajon, 

 during his voyage from France to Cayenne, collected many 

 luminous points in the sea, which he says, when examined 

 by a lens, were found to be minute spheres. They disap. 

 peared in the air. Doctor Le Roy, in sailing from Naples 

 to France, observed the sparkling appearance of the sea, 

 which is usually produced by the medusa scintillans. By 

 filtering the water, he separated luminous particles from it, 

 which he preserved in spirit of wine: they were, he says, 

 Hke the head of a pin, and did not at all resemble the ne- 

 reis noctiluca, described by Vianelli; their colour approach- 

 ed a yellovv brown, and their substance was extremely 

 tender, and fragile. Notwithstanding this striking resem- 

 blance to the medusa scintillans, Le Roy, in consequence 

 of a preconceived theory, did not suppose what he saw 

 were animals, but particles of an oily or bituminous na- 

 ture *. 



The minute globules, seen by Mr. Langstaff in the In- 

 dian ocean, were, I think, in all probability, the scintil- 

 lating species of medusa: and on my showing him some of 

 these animals I have preserved in spirits, he entertained 

 the same opinion. 



Professor Mitchell, of New York, found the luminons 

 appearance on the coast of America, to be occasioned 

 by minute animals, that, from his description, plainly 

 belonged to this species of medusa, notwithstanding 

 which, he supposed them to be a number of^the nereis 

 noctiluca f , 



* Observ. surnine Lumi&re produite par L'Eau delaMer, MSin. 

 Etrang. des Sc. 

 t Phil, Mag. Vol. X, p 20. 



The 



