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cal fishes, and proposed the question, whether the vital 

 property of emitting light was designed for the protection of 

 these animals, or is it connected with the function of genera- 

 tion ? The property of evolving light is not confined to 

 aquatic animals ; some of the terrestrial mollusca, as the 

 limax noctilucus, produce a phosphorescent secretion capa- 

 ble of emitting a light of considerable brilliancy. 



Many insects are luminous, as the several species of 

 elater, the lampyris noctiluca and splendidula, the pausus 

 sphcerocerus, scarabaeus phosphoreus, and the scolopendra 

 electrica. 



The fulgora lanternaria is one of the most remarkable 

 of the class, and during the night diffuses so strong a light, 

 that a few, it is said, being fastened together, are employed 

 to enlighten the path of the traveller, and to guide his foot 

 steps during the darkness of night. Having made a few 

 remarks on the tapetum lucidum existing in the eyes of some 

 animals, the author proceeded to detail the chief object of 

 his communication, namely, facts relative to the develop- 

 ment of light in the living human subject. The first case 

 that he narrated was that of a young lady in the last stage 

 of pulmonary consumption. About ten days previously to 

 her death, there was observed a very extraordinary light 

 which seemed darting about the face, and illuminating all 

 around her head, flashing like an aurora borealis : it was 

 at night, and after a day of extreme nervous agitation pro- 

 duced by debility and the dread of suffocation. This lumi- 

 nous appearance commenced suddenly, and was at first 

 mistaken, by her attendants, for the light of a candle, which 

 was accordingly removed lest it should disturb the slumbers 

 of the patient. The peculiar light, however, continued 

 flitting over her countenance for more than an hour ; its hue 

 was not that of candle light, it was more silvery, like the 

 reflection of moonlight on water. Three nights afterwards 

 it re-appeared, and was observed by additional members of 



