▁en larg ed , ▁and ▁within ▁it ▁the ▁c oc oon ▁is ▁constructed , ▁a ▁small ▁area ▁of ▁the ▁upper ▁cut icle ▁of ▁the ▁leaf ▁at ▁the ▁extreme ▁end ▁of ▁the ▁mine ▁being ▁first ▁prepared ▁to ▁a ▁transparent ▁thin ness ▁for ▁the ▁exit ▁of ▁the ▁pup a ▁later . ▁The ▁fr ass ▁is ▁fin ely ▁gran ular , ▁pale ▁in ▁colour , ▁not ▁very ▁abund ant , ▁and ▁occup ies ▁a ▁rather ▁broad ▁band ▁in ▁the ▁central ▁third ▁of ▁the ▁gallery . ▁ ▁The ▁mine ▁made ▁by ▁the ▁South ▁Island ▁form ▁diff ers ▁somewhat . ▁In ▁the ▁earlier ▁part ▁the ▁mine ▁is ▁a ▁simple ▁verm iform ▁gallery . ▁Later , ▁however , ▁instead ▁of ▁ending ▁in ▁a ▁somewhat ▁tort uous ▁and ▁w iden ed ▁gallery , ▁it ▁exp ands ▁into ▁a ▁relatively ▁large ▁bl ot ch , ▁which ▁may ▁occup y ▁the ▁entire ▁leaf , ▁or ▁all ▁or ▁the ▁greater ▁part ▁of ▁one ▁half ▁of ▁the ▁leaf ▁in ▁larger ▁leaves . ▁The ▁entire ▁mine ▁is ▁on ▁the ▁upper ▁surface ▁of ▁the ▁leaf , ▁and ▁is ▁pale ▁green ▁in ▁colour . ▁The ▁mid rib ▁forms ▁a ▁bar rier ▁in ▁its ▁bas al ▁two - third s . ▁The ▁bl ot ch ▁is ▁irregular ▁in ▁shape , ▁but ▁all ▁irregular ities ▁are ▁rounded . ▁The ▁fr ass ▁is ▁fin ely ▁gran ular , ▁black ▁and ▁sc ant y . ▁Old ▁mines ▁soon ▁become ▁white ▁and ▁consp ic uous . ▁ ▁References ▁ ▁External ▁links ▁The ▁Le af ▁M ining ▁In sect s ▁of ▁New ▁Zealand