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in the shoots of the tree, (2) caterpillar feeding on the green 

 needles, (3), cocoons lying in the ground or among the long grass, 

 (4) adult on the wing. 



2) The larch trees may be examined for signs of Sawfly attack, 

 even though no insect can be found. 



" The caterpillars or larvae of the Large Larch Sawfly may be 

 first looked for towards the middle and end of June. In 1909 the 

 first seen were not discovered till July 4th, but they were evidently 

 some days old and the season was rather late. They appear in 

 considerable number on the lower branches of the larch, generally 

 towards the terminal shoots in which the eggs are laid. As they 

 grow older they advance towards the stem, and eventually may be 

 found wherever there are any needles. Larvae begin to spin up 

 their coccons in July. In 1909 the last caterpillar was seen on 

 August' 3 ist, but in other years they might be found later. 



"When very small they are not easily noticed but they grow 

 rapidly, and when full grown are about three-quarters of an inch 

 long', with round black heads, three pair of black thoracic legs, 

 and seven pairs of abdominal legs of a greyish green, the same 

 colour as the rest of the body. 



" The caterpillars feed at first in clusters, but afterwards they 

 separate in search of food. They assume various characteristic 

 positions, a common one being with their " tail end " curled round 

 the shoot on which they are feeding. When disturbed they erect 

 the hind segments of the body over the front ones. The larvae 

 of the Large Larch Sawfly can be distinguished from other larvae 

 that may be found on the larch by the following characters: 



Moth caterpillars Nematus Erichsonii 



Legs never more than sixteen. The caterpillars have twenty 



If they are geometer caterpillars legs. 



they progress by a looping or The mode of progression in 



spanning movement characteris- continuous, 

 tic of this family. 



Other Sawflies: 



The Nematus Laricis, or Small Has a black bead, and body 



Larch Sawflly caterpillar has a is greyish green, 



brown head, is grass green or Feeds and grows till the end 



greenish brown in colour. It is of August, 

 full grown in July. 



