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XLVI. The Pear Tree Slug. 



1. Find some of the eggs, and if possible some of the females 

 ovipositing. What is the shape of the egg? 



2. How many eggs to a leaf? 



3. Examine larva and its manner of feeding. 



4. Its duration as larva. Number of moults. 



XLVII. The Spruce QalI=Louse. 



1. Examine carefully some infested twigs of white spruce, and de- 

 termine the shape of galls. 



2. Watch for the deposition of eggs in woolly coverings about 

 May 10th. 



3. Draw egg masses. Estimate the number of eggs. 



4. How long before the eggs hatch? 



5. Watch the grey lice for five or six successive days, and deter- 

 mine how the galls are made. 



6- What are the best means of combating the gall-lice? 



XLVin. The Oy«ter=Shell Scale. 



1. Collect specimens of twigs infested with Oyster-Shell scale, 

 and determine what stage of its history the insect is passing through. 



2. Make careful drawings of the adult and young of this insect. 



3. Try to find out how far the young would move from the mother 

 scale before it settles down — about June 1st. 



3. Determine if you can the duration of each moult. 



XLIX. The Larch Saw=Fly. 



1. Search carefully in the soil in the larch grove for dark-brown 

 oval objects, and take them to your room ; place them in a box and 

 await developments. 



2. Describe carefully the adult saw-flies. Any difference between 

 sexes? Pin several for your collection. 



3. Observe the females depositing their eggs. Describe the pro- 

 cess. How many eggs in the froup? Make a drawing of the eggs in 

 place on the twigs. Account for the bending of the twigs. 



4. Determine the duration of the egg stage, the number of mouhs 

 of the larva, the duration of each moulted stage, and any differences 

 between the different moults. Collect specimens of the different moults 

 for your collection. 



