162 AUSTRALIAN WOODBORING COSSIDAE 



It is generally conceded that the earlier lepidopterous larvae 

 were phytophagous, and it is well known that many Hepiali are 

 subterranean feeders. Our previous paper;] dealt with " Austra- 

 lasian Woodboring Hepialidae," we cannot, however, separate 

 Hepialidae into two distinct phylogenetic groups — phytophagous 

 and lignivorous — it seems rather that some Hepialidae inde- 

 pendently from time to time acquired lignivorous habits, in an 

 evolutionary sense these may be regarded as h'gher than those 

 of phytophagous habit. 



We may note, however, there is little difference in actual 

 habits between phytophagous and lignivorous Hepialidae. Sub- 

 terranean species burrow more or less vertically into the earth, 

 and pupate without any cocoon in the vertical larva burrow. 

 Woodborers likewise burrow vertically downwards, the only 

 approach to a pupal cocoon being that a prepupal operculum is 

 constructed, which seals up the vertical bore or the horizontal 

 galleries ; there is also throughout the larval existence an outer 

 (external) cover. 



There was probably little differentiation amongst early 

 Lepidoptera as regards lars'al habits, differentiation accompanied 

 specialisation, and we may trace the habit of existing Lepidoptera, 

 exposed feeders, case bearers, leaf miners, to progenitors whose 

 habits were similar, living in primeval marshlands, where 

 Neuroptera passed their developmental stages in shallow pools, 

 micropterygid-lepidoptera fed among damp mosses, and 

 Kepialidae derived subsistence from the roots of grasses and 

 ferns. Having acquired the habit of feeding in the interior of 

 reeds, as do existing Phragmataecinae, some Cossid progenitors 

 became lignivorous, and their larvae are now almost exclusively 



so. 



• 



Cossidae larvae burrow indifferently up or down in saplings, 

 branches, or trunks of trees of large growth. At an early age* 

 the lava commences to bore, and covers the barrow with an 

 external cover (Zeuzera) or with a loose web (Endoxyla) 

 sometimes a prepupal cover is constructed (Eudoxyla), some 

 pupate without a cocoon, others construct a pupal cocoon. 

 Zeuzerinae do not leave the larval burrow — like Hepialidae — 



I Trans. Royal Soc, Queensland, Vol. XVI. 



* The very earliest stage of the larva is not passed in the wood, and 

 calls for special investigation, as to what is the exact habit when first 

 hatched. 



