▁structure . ▁The ▁pup a ▁stage ▁last s ▁about ▁three ▁weeks . ▁ ▁The ▁flight ▁period ▁is ▁extremely ▁short , ▁a ▁few ▁weeks ▁only , ▁June ▁to ▁August ▁depending ▁on ▁alt itude . ▁ ▁Description ▁ ▁Description ▁in ▁South ▁( 1 9 0 6 ). ▁ ▁Ad ult ▁ ▁W ings pan ▁. ▁" The ▁typical ▁form ▁of ▁this ▁but ter fly , ▁e pi ph ron , ▁Kno ck , ▁has ▁the ▁ta wn y ▁bands ▁un bro ken ▁on ▁the ▁fore ▁wings , ▁and ▁almost ▁so ▁on ▁the ▁h ind ▁wings ; ▁the ▁black ▁d ots ▁on ▁the ▁h ind ▁wings ▁of ▁the ▁female ▁are ▁often ▁pup illed ▁with ▁white , ▁and ▁more ▁rarely ▁this ▁is ▁so ▁in ▁the ▁male ▁also . ▁It ▁has ▁been ▁stated ▁that ▁spec im ens ▁occur ▁in ▁Per th shire ▁which ▁exhib it ▁these ▁characters . ▁All ▁the ▁British ▁examples ▁of ▁the ▁small ▁mountain ▁ring let ▁that ▁I ▁have ▁seen ▁are ▁refer able ▁to ▁the ▁form ▁known ▁as ▁c ass io pe , ▁Fab . ▁( Pl ate ▁ 7 7 ). ▁The ▁ta wn y , ▁or ▁orange , ▁bands ▁are ▁rarely ▁so ▁entire ▁on ▁the ▁fore ▁wings ▁as ▁in ▁e pi ph ron , ▁and ▁are ▁generally ▁rather ▁nar ro wer ; ▁and ▁that ▁on ▁the ▁h ind ▁wing ▁is ▁broken ▁up ▁into ▁three ▁or ▁four ▁rings . ▁The ▁black ▁d ots ▁are ▁usually ▁smaller ▁and ▁without ▁white ▁pup ils . ▁The ▁female ▁is ▁somewhat ▁larger ▁and ▁the ▁bands ▁or ▁rings ▁pal er .