290 Mli. A. G. BUTLER ON THE BUTTERFLIES 



The ants on which we experimented were Formica fusca nud 

 F. cinerea and Gremastogaster scutellaris ; but it was rather too 

 late in the season, and they were somewhat torpid. 



The yellow of the soda- flame certainly affected the Formica 

 cinerea, but the others seemed to take no notice of it. 



The barium also affected the F. cinerea, but neither of the others ; 

 I could not feel sure whether it was the green or the accom- 

 panying yellow which disturbed them. The red of the lithium 

 was not so brilliant, still the F. cinerea seemed to perceive it. 



The strontium-flame did not seem to have any effect on the 

 ants. 



It is obvious that these facts suggest a number of interesting 

 inferences. I must, however, repeat the observations and make 

 others ; but we may at least, I think, conclude from the preceding 

 that :— (1) ants have the power of distinguishing colour ; (2) that 

 they are very sensitive to violet ; and it would also seem (3) that 

 their sensations of colour must be very different from those pro- 

 duced upon us. 



As to the Longevity of Ants. 



I have been much surprised at the longevity of my ants. I 

 have still two queens of Formica fusca* which have been witli me 

 since 1874. They must therefore now be at any rate four years 

 old ; but as they Avere probably a year old when I captured them, 

 they would now be not less than five years old. As regards 

 workers, I have some specimens of Formica sanguinea and F.fusca 

 which M. Eorel was so good as to send me from Munich in the 

 beginning of September 1875, some F. cinerea which 1 brought 

 back from Castellamare in Nov. 1875, and a great many belong- 

 ing to various species which have been with me since 187G. 



On the Butterflies in the Collection of the British Museum 

 hitherto referred to the Genus Euploea of Fabricius. By 

 Arthur Gr. Butler, F.L.S., &c. 



[Bead February 21, 1878.] 



In the year 1866 I published a " Monograph of the Diurnal 

 Lepidoptera belonging to the G-enus Fwploea,''^ in the ' Proceedings 

 of the Zoological Society.' In this memoir I split up the group 

 into arbitrary and, as I now see, very unnatural divisions, over- 

 looking the fact that several natural genera existed. 

 * These ants are still alive, Aug. 1878. 



