Asemilm, striatum and Criocephalas ferus. 171 



in the pupa state about tbree weeks. The pupa is very 

 active. It has no cocoon, but can use the whole of its 

 upward-burrow (up and down which it frequently travels) 

 for the purpose. 



The extremity of its abdomen is provided with two long 

 sharp spines which assist in this operation. 



The way it progresses is interesting. It curls the 

 extremity of its body underneath it, with the result that 

 one of the spines becomes fixed into the side of the 

 burrow. It then straightens itself. This operation con- 

 tinually repeated constitutes its mode of locomotion. 

 Minute down-curved spines on the dorsal side of the 

 abdomen prevent it from slipping down its burrow when 

 stationary. A noteworthy point in reference to these 

 spines is that they are the only hard and dark parts in 

 the pupa immediately after its metamorphosis from the 

 larva. 



Apparently its object in travelling up and down its 

 burrow is to prevent the growth of mildew upon its walls. 

 I have observed that in <j;lass tubes containing these and 

 other Longicorn larva) the galleries when occupied by 

 healthy larva or pupa are immune from mildew, while the 

 other parts of the wood may be badly infested. 



It will be recalled that the pupa of the clear-wing 

 moths are provided with serrations on the margins of their 

 abdominal plates to assist them in travelling up and down 

 their burrows in a similar manner. 



These spines serve an additional purpose, fur they assist 

 the pupa in the initial stages of casting its skin, by enabling 

 it to hold its body more rigid and in greater tension, while 

 splitting open the thin skin at the back of its neck. It 

 will thus be seen how necessary it is in rearing these and 

 allied pupae, to put them in tubes which afford them the 

 same facilities for doing this as their native burrows do. 



I have lost more pupae from exhaustion in seeking to 

 split this thin skin than from any other cause. 



After undergoing its final metamorphosis Asemum 

 matures rather rapidly. 



The imago opens the roof of its prison when almost 

 mature. 



Seeing that their burrows are the only places where one 

 can hope to find these insects, it seems pretty certain 

 that when possible they always hide in them during the 

 daytime, affording as they do such excellent retreats. 



