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eal 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, scarabeeus phosphoreus, and the scolopendra 
electrica. 
The fulgora Janternaria 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 voung 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 
