REPORT OF THE APPLE AND PEAR CONFERENCE. 



57 



the under surface for the egress or ingress of the mites. My 

 specimens of blistered leaves are from Kelso, the first record to 

 my knowledge of gall mites in Scotland. I received them in 

 August last. The mites hibernate in the buds of the tree in 

 winter, and are most difficult of extermination. Collect all 



PEAR MUSSEL SCALE. 



affected leaves in spring, when the mites are still in them, and 

 burn them. When once badly affected the trees continue so 

 from year to year, and unless they are valuable kinds should be 

 grubbed up and burnt to prevent the pest from spreading. Plant 

 healthy trees in their place. I had specimens from another 

 source affected with gall mites, mussel scale, and apparently 

 canker as well. 



Slugworms are the grubs of certain sawflies, differing in 

 colour, and in the nature of the secretion covering their bodies ; 

 but the slugworm proper is the grub of Eriocampa limacina (or 

 the Selandria cerasi of Miss Ormerod). It derives its name 

 from the black slime covering its hairy body till the last moult, 

 when the resinous dark coat is thrown off. The grubs have large 

 heads, and in the earlier stages, when slimy, bear considerable 

 resemblance to a black slug. Hence the derivation of the name 

 slugworm. I collected my specimens on pear trees at Holwood, 

 Kent, the other week. Autumn is the time they make their ap- 

 pearance. They are very voracious, and eat away the upper 

 surface of the leaves, which become brown and ultimately drop, 

 causing the trees to become unhealthy. The fruit was affected 

 with the fungus which causes cracking, were very much split, 

 and entirely useless. The slugworms under notice attack most 



