FIRST REPORT ON ECONOMIC BIOLOGY. 



ground beneath the trees in the winter, and rolling it in the early 

 spring. By this means the pupae are deeply buried, while the rolling 

 hardens and cakes the surface, thereby preventing any few pupae 

 which may have been left near the surface - from making their way 

 through. 



I know of a case where this troublesome pest has been effectually 

 eradicated by turning fowls into the orchard in the months of June and 

 July. A very bad attack was experienced in 1909, but nothing has 

 been seen of the insects during 1910. 



Spraying for a pest of this kind is wasteful and largely ineffective, 

 as also the scattering of kainit on the surface of the ground. 



THE GOOSEBERRY SAWFLY. 



Nematus ribesii, Scop. 



A few cases have been reported upon where the larvae of this 

 insect have occasioned a large amount of damage. 



LlFE-HlSTORY. 



The eggs are laid on the underside of the leaves, and the larvae 

 hatch out in from six to eight days. At first they are very small, 



almost white, w r ith a few black spots 

 anteriorly, and a black head. There are 

 four moults, and after the first one the cater- 

 pillars are greener in colour, and the black 

 spots more numerous. They continue active 

 for about twenty-eight days. On becoming 

 full-fed they usually fall to the ground, enter 

 the earth, and there spin brownish-coloured, 

 oval cocoons. Sometimes the cocoons are 

 found upon the bushes themselves. From 

 these cocoons the flies appear in about 

 twenty-one days. Usually there are three 

 broods during the summer ; the cocoons of 

 t ^ e j ast brood remain in the earth until the 



FIG. 13. THE GOOSEBERRY 



SAWFLY. 

 i and 2. Larva in the two last 



3 . -The Cocoo a n geS ' 4 .-The Fly. spring, and the flies appear early in April. 



PREVENTIVE AND REMEDIAL MEASURES. 



The pupae may easily be destroyed by turning over the soil 

 beneath the bushes in the early spring, or in the case of a few bushes 



