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in being able to answer his question by replying, " Because other 

 people have been more fortunate than yourself, and have seen its 

 beautiful luminosity." Had I possessed no further knowledge of the 

 subject than Mr. Treffry, what had I thought of the following ? — 

 " The so-called lanthorn appears to answer as a drum to reverberate 

 its hum, and as a ' buffer ' to protect it, when in its rapid flight it 



strikes against an obstacle, as it is elastic and horny I think 



its use is what I have stated — an instrument of sound and a ' buffer.' " 

 I am expected to believe that the lamp of the winged torch-bearer is 

 no more than this. No ! do not believe in any such degrading fact. 

 I will bring evidence before you of such weight as to settle the ques- 

 tion of the luminosity of the lantern fly, and restore it to its legitimate 

 position in your minds as a light-bearing insect. 



At a Meeting of the Royal Physical Society of Edinburgh, held 

 November 24th, 1858, a specimen of the lantern fly {Fulgora Later- 

 naria) was exhibited by Dr. J. A. Smith, who observed that it was 

 still an undecided question amongst naturalists whether these flies 

 were really at any time luminous or not. It was therefore of import- 

 ance that the undoubted evidence of eye-witnesses should be pro- 

 duced. Mr. Banks, of Prestonpans, who forwarded the Fulgora to 

 Dr. Smith, was therefore at once requested to obtain further informa- 

 tion from his correspondents on that particular point. 



On the 27th of April, 1859, at a subsequent Meeting of the same 

 Society, Mr. James Banks communicated, through Dr. Smith, the 

 reply of his correspondent at Honduras to the question raised at 

 the Society. Mr. Banks had received various letters upon the sub- 

 ject of the luminosity of Fulgora Laternaria : they all bore testimony 

 to the truth of the statement of this fly really emitting a light. 

 One from Mr. Alexander Henderson, of Belize, furnished the fol- 

 lowing details : — " In answer to the question, ' Is it really luminous ?' 

 certainly the fly possesses light, and therefore emits it. The light is 

 evidently under control, for it increases and diminishes at pleasure. 

 When the wings are closed there are three luminous spots on each 

 side of the head-part, on the upper part (like a cat's staring eyes) of a 

 beautiful sulphur-coloured light, in rays that spread over the room. 

 The third luminous spot is seen when the fly is on its back, half-way 

 down the abdominal part of the insect. When quiescent the lumina- 

 tion is least ; in daylight the upper spots are nearly white, emitting no 

 light whatever (its lively time is at twilight). Immediately on being 

 agitated, or moving about, the spots become sulphur colour, and radi- 

 ate forth streams of hght, clearly seen, although the sun be shining 



