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THE ENT()M()LO(iIST S RECOKD. 



to ascertain whether deopatra has one or more generations yearly. 

 He concludes most positively it has only one. I was surprised on 

 reading this, because for years I have collected this species in Florence, 

 and I have found that very fresh-looking specimens are to be met 

 with in the early spring, as noted also by Simes, that the insect is on 

 the wing in June and again quite commonly in the autumn, after a, 

 long summer period, during which it entirely disappears, and finally 

 that the colour of the underside of the wings is difi'erent in specimens 

 collected during the three periods of flight. All this had led me never 

 to doubt the existence of three generations. In the Ent. Rec. of May 

 15th, 1919, I pointed out that males with a bluish-white underside 

 predominate amongst specimens of all three of the periods, that those 

 with a vivid green underside are only found in the early spring and 

 that those of a uniform yellow or of a reddish ochreous constitute about 

 a quarter of the individuals of the second and third period and are 

 never found in the first. During 1921 both Querci and I directed our 

 attention particularly to the Gunepteryx and, much to our astonishment, 

 I confess, we could find no proofs that they reproduce more than once 

 a year. None of the ova or larvae, so easily found in April and May, 

 were detected later, nor did the young autumn shoots of the lihamnua 

 show any signs of having been attacked ; no copulations were observed 

 in June and, what is more, not a single female was seen on the wing 

 during the third period of flight of the male sex. We next examined 

 carefully all available specimens and we noticed that the very freshest 

 June ones, evidentl}' just emerged, have a velvety or chalky wing 

 surface, which is never seen in those of the two other seasons. We 

 have thus come to the conclusion that, if positive proofs to the con- 

 trary are not found, Kober and Simes must be right in holding there 

 is only one emergence, in the early summer, although it is quite 

 wonderful how some individuals can live from June till April and still 

 have a perfectly fresh look, save for the velvety surface, which they 

 lose. A still more difficult phenomenon to explain is the difference in 

 colour on the underside. The only hypothesis I can make is that when 

 the surface of the wings becomes more smooth and shiny, as noted 

 above, the scales of some parts of the wings acquire a bluish sheen, 

 which, combined with the yellow pigment contained in the scales, 

 turns the yellow individual forms into green ones, thus abolishing the 

 entirely yellow ones of June, still in existence in September, and 

 turning them into the vivid green ones, only found in the early 

 spring. The whitish-blue individuals would, of course, simply 

 become of a less milky and more intense blue and this would corres- 

 pond to the fact that specimens obviously old and worn are more blue 

 than fresh ones. The same remarks would apply to the undersides of 

 the females : those, which are white when they emerge, turn pale blue, 

 so that the white form is never seen in the spring ; those, which are 

 at first whitish-blue, acquire the very intensely blue colour, often to be 

 found after hibernation. In the case of G. rlimuni I had never been 

 quite satisfied as to the existence of three generations ; I had never 

 observed more than two periods of flight in the same locality ; late 

 winter and June in Florence and early spring and end of August to 

 September at Forte dei Marmi, on the Tuscan coast. I had been 

 struck by the difference in the colour of the underside in specimens of 

 these two periods, similar to those of deopatra, and this I had taken to- 



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