19-1 Ji»U[i±\AL, XATi'iriL HIST. SOCIETY OF SIAM Vol. I. 



No male was observed to reply to the flash of a creeping 

 male. 



P. consangidneus, The male gives a double flash in quick 

 succession followed b}'' a pause, then another flash, and so on ; the 

 female replies within a second to the second flash of the male. A 

 particular female would not repl}^ to the flash of a match, but would 

 answer the double flash of a bulb when 20 or 30 feet away ; on a 

 nearer approach she seemed to recognise something unusual and would 

 not reply. 



P. scintillans. The male gives a short single flash, and the female 

 a longer single flash. 



A female would repl}'- to the first flash of a male of P. cou- 

 sanguineus but the latter takes no notice. The female of this species 

 is apterous. 



P. iiiarginellus. The male gives a single short sharp flash yellower 

 than that of P. scintiUan.<f : the female replies with a double flash, the 

 first sharper and brighter than the second and followed at once by the 

 second. The reply is given very quickly after the flash of the male. 



P. castus. The male gives a single flash not so short and sudden 

 as that of P. marginellus ; the female giv^es a single flash very much 

 like that of P. scintillans but delivered immediately after the flash of 

 the male ; there is no distinct pause as in P. pyralis and no indication 

 of doubling as in P. manjinellus. Tiiese last two species are very 

 similar, and indeed by some authorities they have been considered to be 

 merely forms of the same, Mr McDermott admits that he can find no 

 structural difierence between them, but their flash is so distinct that 

 he considers them good species. They are frequently found flying to- 

 gether but no case of interbreeding has been observed though specially 

 watched for. 



Careful observations of this nature, not only upon Fireflies but 

 upon insects of any sort are very bidly wanted. Too often such habits 

 are regarded as merely everyday events of no particular interest, yet out- 

 side the particular region in which the species occur very little is known 

 about them. At the same time it is very necessary that the species of 

 which such habits are recorded should be correctly determined; notes on 

 the habits of any animal only vaguely or loosel}^ specified are of little 

 use, hence it is essential, if any observations are to be of scientific value, 

 that specimens should be collected and their identity definitely establi- 



