GREYISH-HORNED BEETLE OF THE WATTLE. 131 



CHAPTER CXXXI. 



Greyish-Horned Beetle of the Wattle. 

 (Pachydissus sericus, Newman.) 



Order : Coleoptera. Family : Cerambycidce. 



This is a brown Longicorn (long-horned) beetle, with a 

 silvery sheen — a colour very difficult to show correctly in 

 a drawing. This species is very common in many parts 

 of our State, and it has a wide geographical range. In 

 Victoria, it feeds principally upon the wood of the common 

 Black Wattle (Acacia decurrens), to the limbs of which it 

 does great damage. The eggs are deposited by the female 

 on the bark of the tree, and the larvae, when hatched, at 

 once commence to bore through the bark into the wood, 

 where they remain for a long time ; how long is not known. 

 Mr. Froggatt speaks of this pest doing damage to the 

 limbs and branches of A. longifolia, but I have never seen 

 this tree attacked by it, although very susceptible to the 

 attentions of Uracanthus and other wood borers of the 

 Longicorn family. 



The male (Fig. III.) is smaller and narrower than the 

 female, but nearly identical in colour to the latter (Fig. IV.). 

 The mummy-like pupa (Fig. V.) is yellowish- white in 

 colour, and the larva (Fig. II.) is about the same colour 

 as the pupa. 



Fig. I. shows a portion of a cross-section of the common 

 Black Wattle, from which some of the insects illustrated 

 were reared. It has always been a puzzle for me to account 

 for the partiality which many beetles, also other orders and 

 families of insects, have for the bark and wood of the wattle. 

 It is a well-known fact to entomologists that very few 



