FIREFLIES AND GLOW-WORMS AND 
THEIR LIGHT. 
By: Ke iG. BLAIR. BSC. Fes. 
(Assistant ENroMOLOGIST AT THE BritrisH Museum, 
NaturaL History). 
There is perhaps no more striking phenomenon in the insect 
world, than the brilliant and frequently flashing lights exhibited at 
night by the insects popularly known as Fireflies and Glow-worms, 
yet at first sight it is astonishing how little is known to scientists at 
home of the habits of these insects, and of the part played by this 
luminosity in their life history. But when we consider that our 
knowledge of these creatures is almost entirely based on the dried 
specimens of our collections, which are practically never accompanied 
by detailed or in any way critical notes on their habits as observed by 
the collectors, this deficiency in our information on the subject be- 
comes more readily intelligible. 
The lack of co-operation between the systematic student at 
home and the actual collector in the field, whether a trained entomo- 
logist or not, was particularly brought home to me in conversation on 
this subject with my friend Mr. K. G. Gairdner on the occasion of his 
present visit to this country, and it is at his request that these notes 
are written with the express purpose of interesting the members of the 
Natural History Society of Siam in the study of these fascinating 
creatures, and of helping to elucidate the life histories of some of the 
Siamese species. 
With few exceptions, luminous insects throughout the world be- 
long, broadly speaking, to one family of Beetles, the Lampyridae, or 
to give them their popular name, the Fireflies and Glow-worms. The 
most important exception to this statement is afforded by the Fire- 
flies of the West Indies and Central America, locally known as “‘ Cucujos,” 
which, though still Beeties, belong to quite a different family, the 
Llateridue ov Skipjacks. 
