44 PROTECTION OF PLANTS — 1924-25 



the beech trees in the wood were badly attacked, and the ehns also showed signs 

 of slight infestation. At Frelighburg an entire hillside instead of being green 

 was changed to a dull reddish brown and attracted attention even from a long 

 distance. Observations were made at a number of towns and villages in the 

 counties of Missisquoi, Huntingdon and Brome and there was scarcely a place 

 the insect was not to be found in large numbers. 



Former Records 



The first Canadian record of the Maple Leaf Cutter was made in 1872 by 

 Mr. E. Baynes Reed who reported it about London, Ont., as being "unusuaVy 

 noticeable." Dr. Fyles observed an outbreak in Missisquoi County, Que., 

 near Sweetsburg in 1881. Dr. Fletcher, in 1885, recorded it as being severe in 

 Ottawa and instanced four acres of maples near Government House Grounds 

 which were completely defoliated by this pest. In 1887, Dr. Fletcher again 

 referred to it as "continuing to increase to an alarming extent." The only other 

 reference I could find was one by Dr. Hewitt, in his 3rd Annual Report on page 

 182, where he speaks of P. acerifoliella as being very prevalent during the sum- 

 mer of 1911. 



Adult 



The adult is a microlepidopteron of a third of an inch spread, the forewings 

 being bright steel blue and the unders smoky brown. A tuft of yellow hairs on 

 the head gives the moth quite a characteristic and distinctive marking. 



Larva 



The larva when full grown is a quarter of an inch long, flat, cylindric in 

 outline, and dull white in colour. For the first ten days of its existence it works 

 as a miner in the leaf tissues. It then cuts out an oval case from the mine, 

 top and bottom, making the lower half a little larger than the upper. This done 

 it comes to the exterior, turns the case upside down, anchors it with silken threads 

 to the leaf surface and continues to feed from within the protecting covers. 

 When the second covering is to be cut out, the larva projects its head for a short 

 distance beyond the case and makes a narrow slit right around its circular house. 

 The new circle which now supports the old case is prevented from dropping to the 

 ground by the silk threads, and when these are severed the circle is dragged away 

 out of the hole in the leaf, inverted, and secured to the old case to form a new 

 roof. This is done again for the third time, after which the cases fall to the 

 ground where the larvae transform to yellow-brown pupse. From these the 

 moths emerge in swarms during the later part of May to lay their eggs on the 

 underside of the leaves. 



