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is said, is very prevalent in Cheshire on the pear- 

 trees, where it is considered to be injurious to the 

 fruit, as, by clinging to the rind, it prevents the fruit 

 from swelling to its full size. It is asserted that 

 peaches, apricots, plums, &c, suffer from the attacks 

 of the mussel-scale ; and if young Ribston Pippins 

 and some varieties of pears be planted near any other 

 apple or pear-tree that already supports these insects, 

 they will speedily migrate to them. The same ob- 

 server says, " I believe this disease is mostly, if not 

 entirely, confined to wall-fruit in the open air, stand- 

 ards not affording them sufficient warmth and shelter 

 during our winters in Scotland, where they have been 

 very abundant and very troublesome. They attach 

 themselves to the bark, and by means of their ros- 

 trum they soon exhaust a branch so completely of its 

 sap that it withers and dies/ 5 Mr. Ingpen recom- 

 mends " two or three applications in the spring, at 



