378 WOOD moths: with some account of their life-histories, 



bore for upwards of nine years, during which time it crawls back- 

 wards and forwards from the entrance, gnawing and enlarging the 

 diameter, so that the passage of escape is always in proportion to 

 the increasing bulk of the larva. For three months, from the 

 beginning of June till the end of August, it remains in a quies- 

 cent or toi-pid state, without moving or feeding ; at the end of 

 this period it casts its skin, and again commences to feed, this 

 operation being repeated every season, at any rate for the last few 

 years of its larval existence. When the time comes for its meta- 

 morphosis into the chrysalid, it retreats to the apex of the bore, 

 cutting oflf all communication with the intervening space between 

 by placing a stout felted wad or button at the base, the tip of the 

 abdomen of the chrysalid touching the top of the bore, the head 

 pointing downwards and resting against the wad, and enveloped 

 in a thick yellow viscid secretion. 



Changing into a chrysalid in May, the perfect moth emerges 

 early in the following November. Before the moth is ready to 

 come forth, the expansion of the chrysalid dislodges the wad, 

 which falls down the bore, thus liberating the chrysalid, which 

 works its way out to the entrance, protruding through the hole 

 about an inch or more before the skin splits and she crawls out. 



The average depth of the bore is about eight inches, but it may 

 sometimes reach to a foot ; the diameter is about 1 1 inches ; and 

 the fully developed larva about eight inches in length. In spite 

 of the thick protective wad, the chrysalid is frequently killed and 

 devoured by ants. But by far its most destructive enemy is a 

 large beetle, Trogodendron fasciatum (Fam. Cleridae), which Mr. 

 Thornton says, kills a great number of them. 



Mr. Thornton had a larva of this moth under observation for 

 several years, and from time to time watched its movements by 

 cutting out a section of the stem of the living tree, which he re- 

 placed and pegged back each time he examined it, afterwards 

 breeding out the moth, which is now in the Australian Museum 

 from the observed larva. 



