87 



of Temasia Wceberana. The sap, too, is often inju- 

 riously drawn off by a minute coccus, of which the 

 female has the exact shape of a muscle- shell (C. Ar- 

 borum linearis, Geoffr.) y and which Reaumur has ac- 

 curately described and figured. But the greatest 

 enemy of this tree, and which has been known in this 

 country since the year 1787, is the apple-aphis, called 

 by some the coccus, and by others the American 

 blight. This is a minute insect, covered with a long 

 cotton-like wool, transpiring from the pores of its 

 body, which takes its station in the chinks and rugo- 

 sities of the bark, where it increases abundantly, and 

 by constantly drawing off the sap, causes ultimately 

 the destruction of the tree. Whence this pest was 

 first introduced is not certainly known. Sir Joseph 

 Banks traced its origin to a nursery in Sloane Street ; 

 and at first he was led to conclude that it had been 

 imported with some apple-trees from France. On 

 writing, however, to the gardeners in that country, 

 he found it to be wholly unknown there. It was 

 therefore, if not a native insect, most probably de- 

 rived from North America, from whence apple-trees 

 had also been imported by the proprietor of that nur- 

 sery. Whatever its origin, it spread rapidly. At 

 first it was confined to the vicinity of the metropolis, 

 where it destroyed' thousands of trees. But it has 

 now found its way into other parts of the kingdom, 

 particularly into the cider countries ; and in 1810 so 



