172 KOLLIKER, ON LAMPYRIS. 
which the insects appear, the only result at which I arrived 
was, with the aid of the thermo-electrical apparatus, to 
determine that the temperature of the non-luminous females 
was 17°C., in a room at the temperature of 20° C. 
Results. 
From the foregoing experiments, coupled with the anato- 
mical facts, I conclude that the luminous organs are a ner- 
vous apparatus, whose nearest analogues might be sought 
in the electrical organs. All excitants of the nerves excite 
the luminosity, and the agents which annihilate the nervous 
functions, act injuriously in their case also. My experiments 
wholly subvert the theory hitherto current, which assumes 
the existence of a luminous material, secreted and deposited 
in the organs, a sort of phosphorus, which, on the addition of 
oxygen through the respiratory movements, becomes oxy- 
dized, and consequently luminous. It must, indeed, be a 
strange material which may be rendered luminous by acids 
and alkalies, alcohol and creosote, salts and sugar, and has 
its luminosity destroyed by prussic acid and conein. It 
seems to me that the observations above detailed are capable 
of but one explanation, viz., that the light is produced under 
the influence of the nervous system, and in all cases is main- 
tained only for such a period, whether long or short, as the 
nerves, stimulated by the will or otherwise, act upon the 
organs. With respect to the proximate causes of the light, 
I have thought of the electrical light, and on light produced 
by chemical action. Whether the former supposition be 
worth further investigation, or whether it be at all possible— 
by analysis of the greenish light of Lampyris, which micro- 
scopical examination shows to consist of minute sparks—to 
determine whether it be electrical or not, I will not 
venture to decide. I am at present inclined to prefer 
the second hypothesis, which also seems to be sup- 
ported by the fact of the presence of urate of ammonia 
in the luminous organs, as my experiments have shown. 
Admitting that these deposits, from their position and their 
being composed of very minute granules, may add to the 
light of the luminous substance itself, still, seeing that 
their number is very variable, it appears more probable to 
refer their production to molecular changes in the luminous 
matter, and to assume that the latter, which manifestly con- 
sists chiefly of an albuminous substance, and is abundantly 
supphed with oxygen by its numerous trachez, undergoes 
during life a decomposition, one of the ultimate results of 
which is urate of ammonia (NH,O, Ur). 
