508 ` General Notes. © [May, 
hypopus a confirmation of his views that the hypopial stage is not 
caused’by exceptional adverse circumstances, as Mégnin sup- 
oses; but is an ordinary provision of nature to insure the distri- 
bution of the species, which it is intended to call Zyroglyphus 
corticalis. Mr, Michael also called attention to the prevalence of 
Rhizoglyphus robini on Dutch bulbs imported into England in 
1884, and to the destructive nature of that species, and the 
damage it did to hyacinth, dahlia and Eucharis bulbs, &c., and 
recommended that imported bulbs should be carefully examined, 
—English Mechanic. 
FIREFLY Licut.—MM. Aubert and R. Dubois have recently 
made a number of interesting observations on the light emitted 
by “pyrophores,” or fire-bearing insects of the family Elateres, 
genus Pyrophorus. These pyrophores have three luminous 
organs, one situated at the ventral part, and two at the superior 
part of the prothorax. The last are always visible, and were sub- 
mitted to the tests. The light was produced by rubbing the in- 
sect with a light brush, and was examined by means of an ordi- 
nary spectroscope with a prism of very refrangible glass and a 
micrometer. The spectrum was very fine, continuous, and show- | 
- ing neither brilliant nor dark rays. This ‘peculiarity has already 
been pointed out by Pasteur and Gernez, who studied the light 
from a pyrophore belonging to the late Abbé Moigno, editor of 
Les Mondes. The spectrum occupied about seventy-five divisions 
of the micrometer, and extended on the red side to the middle of 
the interval which separates the rays A and B of the solar spec- 
trum, and on the blue side a little beyond the ray E. When the 
intensity of the light varied, its composition changed in a remark- 
able manner. When the brightness diminished the red at 
orange disappeared entirely, and the spectrum consists of gree 
and a little blue and yellow. The green rays lasted longest. The 
contrary took place when the light grew in brightness, the green 
appearing first and spectrum extending a little on the blue and a 
great deal on the red side. The least refrangible rays are, there- 
fore, emitted last. No other luminous source known appears to 
behave in like manner. The only case which bears a resem- 
blance is that of sulphate of strontium becoming phosphorescent 
under the action of light at a glowing temperature. As the tem- 
perature rises, rays less and less refrangible appear in the spec- 
trum, but at the same time, as Edmond Becquerel has shown, the 
' dess refrangible rays disappear. When the light of the organ be- 
_ gins to appear, the central and forward part only of the organ is 
_ luminous. Itis only when the light is very bright that the per- 
iphery of the organ is luminous, and then the red rays are visi- 
oe ble. The light was found to give photographic images on a gela- 
__ tino-bromide plate; the insect being two centimeters from the 
ae plate, and the time of exposure reduced from an hour to five 
_ minutes. The photographs show that the light of the pyrophore 
