24 



ENTOMOLOGICAL SOCIEPy OF ONTARIO. 



{'2) The hardwood also affords food and lodging to various insects. The handsome 

 beetle, Glycobius speciosus Say (Fig- 8) (whose black and yellow^ livery is so suggestive of 

 hornets and stings, but is speciosus notwithstanding) is frequently found in our wood- 

 sheds, having arrived at perfection in the maple, the bast of our fire- 

 wood. 



But theie is a creature that far more extensively assists or 

 accompanies the decay of the hardwood trees. It is one of the Horn- 

 tails, fremex colaniba Linn?eus — an insect belonging to the order 

 hymenoptera. The female Tremex is provided with a strong, 

 black, bristle like ovipositor, which proceeds from the centre of the 

 abdomen, and, when not in use lies extended beneath and beyond 

 that section in a fixed and protecting sheath. In depositing its eggs 

 the creature withdraws the ovipositor from its sheath raises its body 

 and drives the appendage through the bark and into the soft wood, 

 laying its eggs therein. As soon as the young grubs are hatched Fig. s. 



they begin to tunnel the wood, enlarging the bore as they increase in size. By the end 

 of the first season they attain the dimensions of thread worms. The full grown larva is 

 an inch and a half in length and has a waxen appearance. Its mandibles have a ferru- 

 ginous tinge and its spiracles a»'e light brown. The prop-legs are imperfect and the body 

 terminates in a short spine. 



Long observation has led me to believe that the Horn tails and other borers do not 

 attack sound and heallhy trees. I stated this belief in a lecture I gave in the Somerville 

 course some years ago. Since then I have read the Rev. J. G. Wood's " Insects at Home," 

 and I am t^lad to find that some remarks of his bear out my statement. Speaking of the 

 dreaded ScoJytus destructor Olivier of Europe he says : — 



" It is much doubted whether the Scolytus ever attacks a healthy tree, principally, 

 as is conjectured because in such trees the burrows of the insects are filled with sap 

 which not only drives out the beetles but prevents their eggs from being hatched. Still 

 when a tree becomes unhealthy the attacks of the Scolytus prevent it from recovering 

 itself," etc. 



A tree struck by lightning, or broken by the wind, or scorched by fire, or hacked 

 and abused by man is the chosen object of insect spoilers. 



Fig. 10. 



Fife. 9. 

 I have spoken of the waste of hemlock which followed upon the first demands for 

 tanbark. Felled hemlock trees that are not soon sent to the sawyer's, are sure to be 

 confiscated by a sawyer of another kind, Prionus unicolor, as Hirris calls it — the one- 

 coloured sawyer — the Orthosoma brunneum of Forster. (Fig. 9.) For nature not only abhors 

 a vacuum ; she also abhors waste. A standing hemlock in the last stage of its existence 



