182 TREATISE ON THE CULTURE AND 



It would be necessary to have separate divisions in the 

 case for each different species, and to put some earth in the 

 bottom of each dr/ision, which should be moistened occasion- 

 ally, as some of them bury themselves in their chrysalis state, 

 while others adhere to walls, gares, or palings. 



. Fresh leaves should frequently be put in, and the box or 

 case covered with a piece of fine canvas, or gauze, to admit 

 the fresh air. 



At the sam.e time that the trees are cleared of the coccus, 

 aphis, or any other insects, the caterpillars should be carefully 

 looked for and picked off. You will observe, that they shel- 

 ter themselves at the ends of the shoots, in the flowers, and 

 at the bottom of the foot-stalks of the flowers. There are two 

 or three sorts that infest . fruit-trees, two of a brown and one 

 of a green colour. Four years ago the apple-trees suffertcl 

 very much by a blight ; they had all the leaves eaten oft, and, 

 of course, bore no fruit. I first had all the caterpillars care- 

 fuUv picked off : I then cut out the cankered wood, and wash- 

 ed the trees with a mixture of urine, soap-suds, and fresh 

 cow-dung, sufficient to bring it to the consistence of paint, 

 laying it on all over the stems and branches of the trees, par- 

 ticularly where the decayed parts were cut out : After this, 

 the trees recovered in a manner that surprised every one who 

 savf them ; and they still continue in a thriving state, and bear 

 very line fruit. 



In 1795 I used the above method with a great many 

 dwarf apple-trees , and the effect was so visible next season, 

 that all w^ho sav/ them took notice of the great difference be- 

 tween them and tlie remaining trees, which we had left to na- 

 ture ; the latter bearing no fruit, and their leaves being eaten 

 by the caterpillar, while the former have borne fme clean fruit 

 ever since. 



The trees, twenty-five in number, which I left to nature, 

 continued in a sickly state for three years, neither bearing fruit 

 nor putting forth shoots. After the third year I headed them 

 dov/n, scraping the stems and cleaning off the insects ; they 

 are now recovered, having made as fine wood as the others, 

 and are in a healthy flourishing state. 



Fig. 2, Plate 9, represents different states of a kind of 

 moth, whose caterpillar has for many years done great mis- 

 chief among pear-trees on walls. One wall in particular, in 

 Kensington Gardens, was very much hurt every year, for seve- 

 ral years successively. I imagined that it had ht&w the effect 

 of lightning, or a blight; till, on picking off the caterpillars, 

 we found a small sort in its case, sticking to the leaves, as 



